run_squad.py

# coding=utf-8
# Copyright 2018 The Google AI Language Team Authors and The HuggingFace Inc. team.
# Copyright (c) 2018, NVIDIA CORPORATION.  All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
""" Finetuning the library models for question-answering on SQuAD (DistilBERT, Bert, XLM, XLNet)."""


import argparse
import glob
import logging
import os
import random
import timeit

import numpy as np
import torch
from torch.utils.data import DataLoader, RandomSampler, SequentialSampler
from torch.utils.data.distributed import DistributedSampler
from tqdm import tqdm, trange
from torch.utils.data import TensorDataset

from transformers import (
    WEIGHTS_NAME,
    AdamW,
    AlbertConfig,
    AlbertForQuestionAnswering,
    AlbertTokenizer,
    BertConfig,
    BertForQuestionAnswering,
    BertTokenizer,
    DistilBertConfig,
    DistilBertForQuestionAnswering,
    DistilBertTokenizer,
    RobertaConfig,
    RobertaForQuestionAnswering,
    RobertaTokenizer,
    XLMConfig,
    XLMForQuestionAnswering,
    XLMTokenizer,
    XLNetConfig,
    XLNetForQuestionAnswering,
    XLNetTokenizer,
    get_linear_schedule_with_warmup,
    squad_convert_examples_to_features,
    AUTOQABertForQuestionAnswering,
    AUTOQADistilBertForQuestionAnswering,
    InitBertForinit
)
from transformers.data.metrics.squad_metrics import (
    compute_predictions_log_probs,
    compute_predictions_logits,
    squad_evaluate,
)
from transformers.data.processors.squad import SquadResult, SquadV1Processor, SquadV2Processor


try:
    from torch.utils.tensorboard import SummaryWriter
except ImportError:
    from tensorboardX import SummaryWriter

import shutil
import json

logger = logging.getLogger(__name__)

ALL_MODELS = sum(
    (tuple(conf.pretrained_config_archive_map.keys()) for conf in (BertConfig, RobertaConfig, XLNetConfig, XLMConfig)),
    (),
)

MODEL_CLASSES = {
    "bert": (BertConfig, BertForQuestionAnswering, BertTokenizer),
    "initbert": (BertConfig, InitBertForinit, BertTokenizer),
    "distilbert": (DistilBertConfig, DistilBertForQuestionAnswering, DistilBertTokenizer),
    "autobert": (BertConfig, AUTOQABertForQuestionAnswering, BertTokenizer),
    "distilautobert": (DistilBertConfig, AUTOQADistilBertForQuestionAnswering, DistilBertTokenizer),
}


def set_seed(args):
    random.seed(args.seed)
    np.random.seed(args.seed)
    torch.manual_seed(args.seed)
    if args.n_gpu > 0:
        torch.cuda.manual_seed_all(args.seed)


def to_list(tensor):
    return tensor.detach().cpu().tolist()


def train(args, train_dataset, model, tokenizer):
    """ Train the model """
    if args.local_rank in [-1, 0]:
        tb_writer = SummaryWriter("logs/squad2_log/" + args.output_dir[args.output_dir.find('/')+1:])

    args.train_batch_size = args.per_gpu_train_batch_size * max(1, args.n_gpu)
    train_sampler = RandomSampler(train_dataset) if args.local_rank == -1 else DistributedSampler(train_dataset)
    train_dataloader = DataLoader(train_dataset, sampler=train_sampler, batch_size=args.train_batch_size, num_workers=1)

    if args.max_steps > 0:
        t_total = args.max_steps
        args.num_train_epochs = args.max_steps // (len(train_dataloader) // args.gradient_accumulation_steps) + 1
    else:
        t_total = len(train_dataloader) // args.gradient_accumulation_steps * args.num_train_epochs

    # Prepare optimizer and schedule (linear warmup and decay)
    no_decay = ["bias", "LayerNorm.weight"]
    optimizer_grouped_parameters = [
        {
            "params": [p for n, p in model.named_parameters() if not any(nd in n for nd in no_decay)],
            "weight_decay": args.weight_decay,
        },
        {"params": [p for n, p in model.named_parameters() if any(nd in n for nd in no_decay)], "weight_decay": 0.0},
    ]
    optimizer = AdamW(optimizer_grouped_parameters, lr=args.learning_rate, eps=args.adam_epsilon)
    if args.warmup_steps==-1:
        args.warmup_steps = int(t_total*0.1)
    scheduler = get_linear_schedule_with_warmup(
        optimizer, num_warmup_steps=args.warmup_steps, num_training_steps=t_total
    )

    # Check if saved optimizer or scheduler states exist
    if os.path.isfile(os.path.join(args.model_name_or_path, "optimizer.pt")) and os.path.isfile(
        os.path.join(args.model_name_or_path, "scheduler.pt")
    ):
        # Load in optimizer and scheduler states
        optimizer.load_state_dict(torch.load(os.path.join(args.model_name_or_path, "optimizer.pt")))
        scheduler.load_state_dict(torch.load(os.path.join(args.model_name_or_path, "scheduler.pt")))

    if args.fp16:
        try:
            from apex import amp
        except ImportError:
            raise ImportError("Please install apex from https://www.github.com/nvidia/apex to use fp16 training.")

        model, optimizer = amp.initialize(model, optimizer, opt_level=args.fp16_opt_level)

    # multi-gpu training (should be after apex fp16 initialization)
    if args.n_gpu > 1:
        model = torch.nn.DataParallel(model)

    # Distributed training (should be after apex fp16 initialization)
    if args.local_rank != -1:
        model = torch.nn.parallel.DistributedDataParallel(
            model, device_ids=[args.local_rank], output_device=args.local_rank, find_unused_parameters=True
        )

    # Train!
    logger.info("***** Running training *****")
    logger.info("  Num examples = %d", len(train_dataset))
    logger.info("  Num Epochs = %d", args.num_train_epochs)
    logger.info("  Instantaneous batch size per GPU = %d", args.per_gpu_train_batch_size)
    logger.info(
        "  Total train batch size (w. parallel, distributed & accumulation) = %d",
        args.train_batch_size
        * args.gradient_accumulation_steps
        * (torch.distributed.get_world_size() if args.local_rank != -1 else 1),
    )
    logger.info("  Gradient Accumulation steps = %d", args.gradient_accumulation_steps)
    logger.info("  Total optimization steps = %d", t_total)

    global_step = 1
    epochs_trained = 0
    steps_trained_in_current_epoch = 0

    tr_loss, logging_loss = 0.0, 0.0
    model.zero_grad()
    train_iterator = trange(
        epochs_trained, int(args.num_train_epochs), desc="Epoch", disable=args.local_rank not in [-1, 0]
    )
    # Added here for reproductibility
    set_seed(args)
    best_f1 = 0
    for _ in train_iterator:
        epoch_iterator = tqdm(train_dataloader, desc="Iteration", disable=args.local_rank not in [-1, 0])
        for step, batch in enumerate(epoch_iterator):

            # Skip past any already trained steps if resuming training
            if steps_trained_in_current_epoch > 0:
                steps_trained_in_current_epoch -= 1
                continue

            model.train()
            batch = tuple(t.to(args.device) for t in batch)

            inputs = {
                "input_ids": batch[0],
                "attention_mask": batch[1],
                "token_type_ids": None if args.model_type in ["xlm", "roberta", "distilbert"] else batch[2],
                "start_positions": batch[3],
                "end_positions": batch[4],
            }

            if args.model_type in ["distilbert"]:
                inputs.pop('token_type_ids')

            outputs = model(**inputs)
            # model outputs are always tuple in transformers (see doc)
            qa_loss = outputs[0]
            
            loss = qa_loss 
            if args.n_gpu > 1:
                loss = loss.mean()  # mean() to average on multi-gpu parallel (not distributed) training


            if args.gradient_accumulation_steps > 1:
                loss = loss / args.gradient_accumulation_steps

            if args.fp16:
                with amp.scale_loss(loss, optimizer) as scaled_loss:
                    scaled_loss.backward()
            else:
                loss.backward()

            tr_loss += loss.item()
            if (step + 1) % args.gradient_accumulation_steps == 0:
                if args.fp16:
                    torch.nn.utils.clip_grad_norm_(amp.master_params(optimizer), args.max_grad_norm)
                else:
                    torch.nn.utils.clip_grad_norm_(model.parameters(), args.max_grad_norm)

                optimizer.step()
                scheduler.step()  # Update learning rate schedule
                model.zero_grad()
                global_step += 1

                # Log metrics
                if args.local_rank in [-1, 0] and args.logging_steps > 0 and global_step % args.logging_steps == 0:
                    # Only evaluate when single GPU otherwise metrics may not average well
                    tb_writer.add_scalar("lr", scheduler.get_lr()[0], global_step)
                    tb_writer.add_scalar("loss", (tr_loss - logging_loss) / args.logging_steps, global_step)
                    logging_loss = tr_loss

                # Save model checkpoint
                if args.local_rank in [-1, 0] and (args.save_steps > 0 and (global_step % args.save_steps == 0)):
                    update = True
                    if args.evaluate_during_training:
                        results = evaluate(args, model, tokenizer)
                        f1 = results['f1']
                        print ('F1:', f1)

                        for key, value in results.items():
                            tb_writer.add_scalar("eval_{}".format(key), value, global_step)
                        if f1 > best_f1:
                            exact = results['exact']
                            print ('best Exact:', exact, 'F1:', f1)
                            best_f1 = f1
                        else:
                            update = False
                    if update:
                        output_dir = os.path.join(args.output_dir, "checkpoint-{}".format(global_step))
                        if not os.path.exists(output_dir):
                            os.makedirs(output_dir)
                        # Take care of distributed/parallel training
                        model_to_save = model.module if hasattr(model, "module") else model
                        model_to_save.save_pretrained(output_dir)
                        tokenizer.save_pretrained(output_dir)

                        torch.save(args, os.path.join(output_dir, "training_args.bin"))
                        logger.info("Saving model checkpoint to %s", output_dir)

                        torch.save(optimizer.state_dict(), os.path.join(output_dir, "optimizer.pt"))
                        torch.save(scheduler.state_dict(), os.path.join(output_dir, "scheduler.pt"))
                        logger.info("Saving optimizer and scheduler states to %s", output_dir)


            if args.max_steps > 0 and global_step > args.max_steps:
                epoch_iterator.close()
                break
        if args.max_steps > 0 and global_step > args.max_steps:
            train_iterator.close()
            break

    if args.local_rank in [-1, 0]:
        tb_writer.close()

    return global_step, tr_loss / global_step



def train_rl(args, train_dataset, model, tokenizer):
    """ Train the model """
    if args.local_rank in [-1, 0]:
        tb_writer = SummaryWriter("logs/squad2_log/" + args.output_dir[args.output_dir.find('/')+1:])

    args.train_batch_size = args.per_gpu_train_batch_size * max(1, args.n_gpu)

    train_sampler = RandomSampler(train_dataset) if args.local_rank == -1 else DistributedSampler(train_dataset)

    train_dataloader = DataLoader(train_dataset, sampler=train_sampler, batch_size=args.train_batch_size, num_workers=1)

    if args.max_steps > 0:
        t_total = args.max_steps
        args.num_train_epochs = args.max_steps // (len(train_dataloader) // args.gradient_accumulation_steps) + 1
    else:
        t_total = len(train_dataloader) // args.gradient_accumulation_steps * args.num_train_epochs


    train_params = []
    for n, p in model.named_parameters():        
        if n.find('linear_1')!=-1 or n.find('linear_2')!=-1 or n.find('linear_3')!=-1 \
            or n.find('linear_4')!=-1 or n.find('linear_5')!=-1 \
                or n.find('linear_6')!=-1 or n.find('linear_7')!=-1  \
                    or n.find('linear_7')!=-1 or n.find('linear_8')!=-1 :
            train_params.append((n, p))
            print (n)
        else:
            p.requires_grad = False

    no_decay = ["bias", "LayerNorm.weight"]
    optimizer_grouped_parameters = [
        {
            "params": [p for n, p in train_params if not any(nd in n for nd in no_decay)],
            "weight_decay": args.weight_decay,
        },
        {"params": [p for n, p in train_params if any(nd in n for nd in no_decay)], "weight_decay": 0.0},
    ]
    optimizer = AdamW(optimizer_grouped_parameters, lr=args.learning_rate, eps=args.adam_epsilon)
    if args.warmup_steps==-1:
        args.warmup_steps = int(t_total*0.1)
    scheduler = get_linear_schedule_with_warmup(
        optimizer, num_warmup_steps=args.warmup_steps, num_training_steps=t_total
    )

    if args.fp16:
        try:
            from apex import amp
        except ImportError:
            raise ImportError("Please install apex from https://www.github.com/nvidia/apex to use fp16 training.")

        model, optimizer = amp.initialize(model, optimizer, opt_level=args.fp16_opt_level)

    # multi-gpu training (should be after apex fp16 initialization)
    if args.n_gpu > 1:
        model = torch.nn.DataParallel(model)

    # Distributed training (should be after apex fp16 initialization)
    if args.local_rank != -1:
        model = torch.nn.parallel.DistributedDataParallel(
            model, device_ids=[args.local_rank], output_device=args.local_rank, find_unused_parameters=True
        )

    # Train!
    logger.info("***** Running training *****")
    logger.info("  Num examples = %d", len(train_dataset))
    logger.info("  Num Epochs = %d", args.num_train_epochs)
    logger.info("  Instantaneous batch size per GPU = %d", args.per_gpu_train_batch_size)
    logger.info(
        "  Total train batch size (w. parallel, distributed & accumulation) = %d",
        args.train_batch_size
        * args.gradient_accumulation_steps
        * (torch.distributed.get_world_size() if args.local_rank != -1 else 1),
    )
    logger.info("  Gradient Accumulation steps = %d", args.gradient_accumulation_steps)
    logger.info("  Total optimization steps = %d", t_total)

    global_step = 0
    epochs_trained = 0

    tr_loss, logging_loss = 0.0, 0.0
    tr_selector_loss, logging_selector_loss = 0.0, 0.0
    tr_dL, logging_dL = 0.0, 0.0

    model.zero_grad()
    train_iterator = trange(
        epochs_trained, int(args.num_train_epochs), desc="Epoch", disable=args.local_rank not in [-1, 0]
    )

    # Added here for reproductibility
    set_seed(args)
    best_f1 = 0
    sample_K = 8

    for _ in train_iterator:
        epoch_iterator = tqdm(train_dataloader, desc="Iteration", disable=args.local_rank not in [-1, 0])
        for step, batch in enumerate(epoch_iterator):
            bsz = batch[0].size(0)
            
            if sample_K > 1:
                new_batch = []
                for t in batch:
                    tmp = []
                    for j in range(sample_K):
                        tmp.append(t)
                    tmp = torch.cat( tmp, dim=0)
                    new_batch.append(tmp)

                batch = new_batch


            batch = tuple(t.to(args.device) for t in batch)


            copy_rate = torch.zeros(bsz*sample_K)
            if global_step < args.guide_rate*t_total:
                copy_rate[:bsz] = 1
            copy_rate = copy_rate.to(args.device)          

            model.train()

            inputs = {
                "input_ids": batch[0],
                "attention_mask": batch[1],
                "token_type_ids": None if args.model_type in ["xlm", "roberta", "distilbert", "distilautobert"] else batch[2],
                "start_positions": batch[3],
                "end_positions": batch[4],
                "copy_rate": copy_rate, 
                "tokens_prob": batch[-1],
            }
            if args.model_type in ["distilbert", "distilautobert"]:
                inputs.pop('token_type_ids')

            outputs = model(**inputs)
            

            loss = outputs[0]
            output_selector_loss = outputs[1]
            lens = outputs[4]

            L = len(loss)
            qa_loss = sum(loss) / L
            reduction_times = len(lens)

            bsz = L // sample_K
            rewards = []
            for i in range(bsz):
                rewards.append([])
            dLs = []
            for i in range(L):
                delta_L = 0
                for j in range(reduction_times):
                    delta_L += lens[j][i].item()

                delta_L /= reduction_times
                reward = -loss[i].item() - args.alpha * delta_L
                rewards[i % bsz].append( reward)
                dLs.append(delta_L)
            mean_dl = sum(dLs)/len(dLs)
            if args.gradient_accumulation_steps > 1:
                mean_dl = mean_dl / args.gradient_accumulation_steps

            tr_dL += mean_dl

            selector_loss = 0
            for i in range(bsz):
                rs = rewards[i]
                rs = np.array(rs)
                baseline = np.mean(rs)

                for j in range(sample_K):
                    reward = (rs[j] - baseline) #/ std
                    selector_loss += reward * output_selector_loss[j*bsz+i]
            selector_loss = selector_loss / L 
            loss = selector_loss 
            
            if args.gradient_accumulation_steps > 1:
                loss = loss / args.gradient_accumulation_steps

            if args.fp16:
                with amp.scale_loss(loss, optimizer) as scaled_loss:
                    scaled_loss.backward()
            else:
                loss.backward()

            tr_loss += qa_loss.item()
            tr_selector_loss += selector_loss.item()
            if (step + 1) % args.gradient_accumulation_steps == 0:
                if args.fp16:
                    torch.nn.utils.clip_grad_norm_(amp.master_params(optimizer), args.max_grad_norm)
                else:
                    torch.nn.utils.clip_grad_norm_(model.parameters(), args.max_grad_norm)

                optimizer.step()
                scheduler.step()  # Update learning rate schedule
                model.zero_grad()
                global_step += 1

                # Log metrics
                if args.local_rank in [-1, 0] and args.logging_steps > 0 and global_step % args.logging_steps == 0:
                    # Only evaluate when single GPU otherwise metrics may not average well

                    tb_writer.add_scalar("lr", scheduler.get_lr()[0], global_step)
                    tb_writer.add_scalar("loss", (tr_loss - logging_loss) / args.logging_steps, global_step)
                    logging_loss = tr_loss

                    tb_writer.add_scalar("selector_loss", (tr_selector_loss - logging_selector_loss) / args.logging_steps, global_step)
                    logging_selector_loss = tr_selector_loss


                    tb_writer.add_scalar("dL", (tr_dL - logging_dL) / args.logging_steps, global_step)
                    logging_dL = tr_dL

                if args.local_rank in [-1, 0] and (args.save_steps > 0 and global_step % args.save_steps == 0):
                    if args.evaluate_during_training:
                        results = evaluate(args, model, tokenizer)
                        f1 = results['f1']
                        print (f1)
                        for key, value in results.items():
                            tb_writer.add_scalar("eval_{}".format(key), value, global_step)
                        if f1 > best_f1:
                            print ('Best F1:', f1)
                            best_f1 = f1
                    output_dir = os.path.join(args.output_dir, "checkpoint-{}".format(global_step))
                    if not os.path.exists(output_dir):
                        os.makedirs(output_dir)
                    # Take care of distributed/parallel training
                    model_to_save = model.module if hasattr(model, "module") else model
                    model_to_save.save_pretrained(output_dir)
                    tokenizer.save_pretrained(output_dir)

                    torch.save(args, os.path.join(output_dir, "training_args.bin"))
                    logger.info("Saving model checkpoint to %s", output_dir)

                    torch.save(optimizer.state_dict(), os.path.join(output_dir, "optimizer.pt"))
                    torch.save(scheduler.state_dict(), os.path.join(output_dir, "scheduler.pt"))
                    logger.info("Saving optimizer and scheduler states to %s", output_dir)

            if args.max_steps > 0 and global_step > args.max_steps:
                epoch_iterator.close()
                break
        if args.max_steps > 0 and global_step > args.max_steps:
            train_iterator.close()
            break

    if args.local_rank in [-1, 0]:
        tb_writer.close()

    return global_step, tr_loss / global_step


def evaluate_logits(args, model, tokenizer, prefix="", evaluate=False):
    dataset = load_and_cache_examples(args, tokenizer, evaluate=False, output_examples=False)

    if not os.path.exists(args.output_dir) and args.local_rank in [-1, 0]:
        os.makedirs(args.output_dir)

    args.eval_batch_size = args.per_gpu_eval_batch_size * max(1, args.n_gpu)

    # Note that DistributedSampler samples randomly
    eval_sampler = SequentialSampler(dataset)
    eval_dataloader = DataLoader(dataset, sampler=eval_sampler, batch_size=args.eval_batch_size, num_workers=1)

    # multi-gpu evaluate
    if args.n_gpu > 1 and not isinstance(model, torch.nn.DataParallel):
        model = torch.nn.DataParallel(model)

    # Eval!
    logger.info("***** Running evaluation {} *****".format(prefix))
    logger.info("  Num examples = %d", len(dataset))
    logger.info("  Batch size = %d", args.eval_batch_size)


    # start_flag = False
    # start_time = None
    start_time = timeit.default_timer() 
    all_logits = []
    for batch in tqdm(eval_dataloader, desc="Evaluating"):
        model.eval()
        batch = list(t.to(args.device) for t in batch)

        with torch.no_grad():

            inputs = {
                "input_ids": batch[0],
                "attention_mask": batch[1],
                "token_type_ids": None if args.model_type in ["xlm", "roberta", "distilbert", "distilautobert"] else batch[2],
            }


            if args.model_type in ["distilbert",  "distilautobert"]:
                inputs.pop("token_type_ids")

            outputs = model(**inputs)


            start_logits = outputs[0]
            end_logits = outputs[1]
            logits = torch.cat([start_logits.unsqueeze(1), end_logits.unsqueeze(1)], dim=1)
            logits = logits.cpu().numpy()
            all_logits.append(logits)

    evalTime = timeit.default_timer() - start_time
    logger.info("  Evaluation done in total %f secs (%f sec per example)", evalTime, evalTime / (len(dataset)-1))


    all_logits = np.concatenate(all_logits, axis=0)
    print (all_logits.shape)
    np.save("npy_folder/squad_logits.npy", all_logits)

    return {}


def load_and_cache_examples(args, tokenizer, evaluate=False, output_examples=False):
    if args.local_rank not in [-1, 0] and not evaluate:
        # Make sure only the first process in distributed training process the dataset, and the others will use the cache
        torch.distributed.barrier()

    # Load data features from cache or dataset file
    input_dir = args.data_dir if args.data_dir else "."
    cached_features_file = os.path.join(
        input_dir,
        "cached_{}_{}".format(
            "dev" if evaluate else "train",
            str(args.max_seq_length),
        ),
    )
    if args.do_lower_case:
        cached_features_file += '_lower'

    # Init features and dataset from cache if it exists
    print (cached_features_file)
    if os.path.exists(cached_features_file) and not args.overwrite_cache and not output_examples:
        logger.info("Loading features from cached file %s", cached_features_file)
        features_and_dataset = torch.load(cached_features_file)
        features, dataset = features_and_dataset["features"], features_and_dataset["dataset"]
    else:
        logger.info("Creating features from dataset file at %s", input_dir)

        if not args.data_dir and ((evaluate and not args.predict_file) or (not evaluate and not args.train_file)):
            try:
                import tensorflow_datasets as tfds
            except ImportError:
                raise ImportError("If not data_dir is specified, tensorflow_datasets needs to be installed.")

            if args.version_2_with_negative:
                logger.warn("tensorflow_datasets does not handle version 2 of SQuAD.")

            tfds_examples = tfds.load("squad")
            examples = SquadV1Processor().get_examples_from_dataset(tfds_examples, evaluate=evaluate)
        else:
            processor = SquadV2Processor() if args.version_2_with_negative else SquadV1Processor()
            if evaluate:
                examples = processor.get_dev_examples(args.data_dir, filename=args.predict_file)
            else:
                examples = processor.get_train_examples(args.data_dir, filename=args.train_file)
        
        # examples = examples[:10]
        features, dataset = squad_convert_examples_to_features(
            examples=examples,
            tokenizer=tokenizer,
            max_seq_length=args.max_seq_length,
            doc_stride=args.doc_stride,
            max_query_length=args.max_query_length,
            is_training=not evaluate,
            return_dataset="pt",
            threads=args.threads,
        )

        if args.local_rank in [-1, 0]:
            logger.info("Saving features into cached file %s", cached_features_file)
            torch.save({"features": features, "dataset": dataset}, cached_features_file)

    if args.local_rank == 0 and not evaluate:
        # Make sure only the first process in distributed training process the dataset, and the others will use the cache
        torch.distributed.barrier()

    if not evaluate:
        if args.model_type.find('distil')!=-1:
            model_type = 'distilbert'
        else:
            model_type = 'bert'

        if args.train_rl:
            tmp  = list(dataset.tensors)

            tokens_prob = np.load(os.path.join("npy_folder", "squad_" + model_type + "_"+ str(args.max_seq_length)+ "_score.npy"))
            tokens_prob = torch.from_numpy(tokens_prob)
            print (tokens_prob.shape)
            
            tmp.append(tokens_prob)
            dataset = TensorDataset(*tmp)

        elif args.train_init:
            tmp  = list(dataset.tensors)

            tokens_rank = np.load(os.path.join("npy_folder", "squad_" + model_type + "_"+ str(args.max_seq_length)+ "_rank.npy"))
            tokens_rank = torch.from_numpy(tokens_rank)
            print (tokens_rank.shape)
            tmp.append(tokens_rank)

            dataset = TensorDataset(*tmp)
        elif args.train_teacher:

            tmp  = list(dataset.tensors)
            teacher_logits = np.load(args.teacher_npy_path)    
            teacher_logits = torch.from_numpy(teacher_logits)    # num_ins, 2, seq_len
            print ('load teacher_logits')
            tmp.append(teacher_logits)

            dataset = TensorDataset(*tmp)

    if output_examples:
        return dataset, examples, features
    return dataset

def evaluate_grad(args, model, tokenizer, prefix="", evaluate=False):
    dataset = load_and_cache_examples(args, tokenizer, evaluate=False, output_examples=False)

    if not os.path.exists(args.output_dir) and args.local_rank in [-1, 0]:
        os.makedirs(args.output_dir)

    args.eval_batch_size = args.per_gpu_eval_batch_size * max(1, args.n_gpu)

    # Note that DistributedSampler samples randomly
    eval_sampler = SequentialSampler(dataset)
    eval_dataloader = DataLoader(dataset, sampler=eval_sampler, batch_size=args.eval_batch_size)

    # multi-gpu evaluate
    if args.n_gpu > 1 and not isinstance(model, torch.nn.DataParallel):
        model = torch.nn.DataParallel(model)

    # Eval!
    logger.info("***** Running evaluation {} *****".format(prefix))
    logger.info("  Num examples = %d", len(dataset))
    logger.info("  Batch size = %d", args.eval_batch_size)

    if args.model_type=='distilbert':
        output_dims = [0, 2]
        back_r = 4
    elif args.model_type=='bert':
        output_dims = [0, 5]
        back_r = 8
    else:
        assert(False)

    max_seq_length = args.max_seq_length
    layers_scores = np.zeros((len(dataset), len(output_dims), max_seq_length), dtype=np.float32)
    cnt = 0

    for batch in tqdm(eval_dataloader, desc="Evaluating"):
        model.eval()
        batch = tuple(t.to(args.device) for t in batch)


        inputs = {
            "input_ids": batch[0],
            "attention_mask": batch[1],
            "token_type_ids": None if args.model_type in ["xlm", "roberta", "distilbert"] else batch[2],
            "start_positions": batch[3],
            "end_positions": batch[4],

        }

        # XLNet and XLM use more arguments for their predictions
        if args.model_type in ["xlnet", "xlm"]:
            inputs.update({"cls_index": batch[4], "p_mask": batch[5]})
        if args.model_type in ["xlm", "roberta", "distilbert"]:
            inputs.pop("token_type_ids")
        outputs = model(**inputs)
        loss = outputs[0]
        hidden_states = outputs[3][1:] 
        last_val = hidden_states[back_r]

        grads = torch.autograd.grad(loss, [last_val, ])
        grad_delta = grads[0] 

        for idx_idx, idx in enumerate(output_dims):                
            with torch.no_grad():
                delta = last_val - hidden_states[idx]
                dot = torch.einsum("bli,bli->bl", [grad_delta, delta])
                score = dot.abs()  # (bsz, seq_len)
                score = score.view(-1, max_seq_length).detach()                    

            score = score.cpu().numpy()
            layers_scores[cnt: cnt+score.shape[0], idx_idx] = score
        cnt += score.shape[0]

    np.save(os.path.join("npy_folder", "squad_" + args.model_type + "_"+ str(max_seq_length)+ "_score.npy"), layers_scores)

    return {}

def train_both(args, train_dataset, model, tokenizer):
    """ Train the model """
    if args.local_rank in [-1, 0]:
        tb_writer = SummaryWriter("logs/squad2_log/" + args.output_dir[args.output_dir.find('/')+1:])

    args.train_batch_size = args.per_gpu_train_batch_size * max(1, args.n_gpu)

    train_sampler = RandomSampler(train_dataset) if args.local_rank == -1 else DistributedSampler(train_dataset)

    train_dataloader = DataLoader(train_dataset, sampler=train_sampler, batch_size=args.train_batch_size, num_workers=1)

    if args.max_steps > 0:
        t_total = args.max_steps
        args.num_train_epochs = args.max_steps // (len(train_dataloader) // args.gradient_accumulation_steps) + 1
    else:
        t_total = len(train_dataloader) // args.gradient_accumulation_steps * args.num_train_epochs


    no_decay = ["bias", "LayerNorm.weight"]
    optimizer_grouped_parameters = [
        {
            "params": [p for n, p in model.named_parameters() if not any(nd in n for nd in no_decay)],
            "weight_decay": args.weight_decay,
        },
        {"params": [p for n, p in model.named_parameters() if any(nd in n for nd in no_decay)], "weight_decay": 0.0},
    ]
    optimizer = AdamW(optimizer_grouped_parameters, lr=args.learning_rate, eps=args.adam_epsilon)
    if args.warmup_steps==-1:
        args.warmup_steps = int(t_total*0.1)
    scheduler = get_linear_schedule_with_warmup(
        optimizer, num_warmup_steps=args.warmup_steps, num_training_steps=t_total
    )

    if args.fp16:
        try:
            from apex import amp
        except ImportError:
            raise ImportError("Please install apex from https://www.github.com/nvidia/apex to use fp16 training.")

        model, optimizer = amp.initialize(model, optimizer, opt_level=args.fp16_opt_level)

    # multi-gpu training (should be after apex fp16 initialization)
    if args.n_gpu > 1:
        model = torch.nn.DataParallel(model)

    # Distributed training (should be after apex fp16 initialization)
    if args.local_rank != -1:
        model = torch.nn.parallel.DistributedDataParallel(
            model, device_ids=[args.local_rank], output_device=args.local_rank, find_unused_parameters=True
        )

    # Train!
    logger.info("***** Running training *****")
    logger.info("  Num examples = %d", len(train_dataset))
    logger.info("  Num Epochs = %d", args.num_train_epochs)
    logger.info("  Instantaneous batch size per GPU = %d", args.per_gpu_train_batch_size)
    logger.info(
        "  Total train batch size (w. parallel, distributed & accumulation) = %d",
        args.train_batch_size
        * args.gradient_accumulation_steps
        * (torch.distributed.get_world_size() if args.local_rank != -1 else 1),
    )
    logger.info("  Gradient Accumulation steps = %d", args.gradient_accumulation_steps)
    logger.info("  Total optimization steps = %d", t_total)

    global_step = 0
    epochs_trained = 0

    tr_loss, logging_loss = 0.0, 0.0
    tr_selector_loss, logging_selector_loss = 0.0, 0.0
    tr_dL, logging_dL = 0.0, 0.0

    model.zero_grad()
    train_iterator = trange(
        epochs_trained, int(args.num_train_epochs), desc="Epoch", disable=args.local_rank not in [-1, 0]
    )
    # Added here for reproductibility
    set_seed(args)
    best_f1 = 0
    sample_K = 8

    for _ in train_iterator:
        epoch_iterator = tqdm(train_dataloader, desc="Iteration", disable=args.local_rank not in [-1, 0])
        for step, batch in enumerate(epoch_iterator):
            bsz = batch[0].size(0)
            

            new_batch = []
            for t in batch:
                tmp = []
                for j in range(sample_K):
                    tmp.append(t)
                tmp = torch.cat( tmp, dim=0)
                new_batch.append(tmp)
            batch = new_batch


            batch = tuple(t.to(args.device) for t in batch)


            copy_rate = torch.zeros(bsz*sample_K)

            model.train()

            inputs = {
                "input_ids": batch[0],
                "attention_mask": batch[1],
                "token_type_ids": None if args.model_type in ["xlm", "roberta", "distilbert",  "distilautobert"] else batch[2],
                "start_positions": batch[3],
                "end_positions": batch[4],
                "copy_rate": copy_rate, 
            }
            if args.model_type in ["distilbert",  "distilautobert"]:
                inputs.pop('token_type_ids')

            if args.train_teacher:
                inputs['teacher_logits'] = batch[-1]

            outputs = model(**inputs)
            
            loss = outputs[0]
            output_selector_loss = outputs[1]
            lens = outputs[4]

            L = len(loss)
            qa_loss = sum(loss) / L
            reduction_times = len(lens)

            bsz = L // sample_K
            rewards = []
            for i in range(bsz):
                rewards.append([])
            dLs = []

            for i in range(L):
                delta_L = 0
                for j in range(reduction_times):
                    delta_L += lens[j][i].item()
                delta_L /= reduction_times
                reward = -loss[i].item() - args.alpha * delta_L 
                rewards[i % bsz].append( reward)
                dLs.append(delta_L)
            mean_dl = sum(dLs)/len(dLs)
            if args.gradient_accumulation_steps > 1:
                mean_dl = mean_dl / args.gradient_accumulation_steps


            tr_dL += mean_dl

            selector_loss = 0
            for i in range(bsz):
                rs = rewards[i]
                rs = np.array(rs)
                baseline = np.mean(rs)
                # std = np.std(rs)
                for j in range(sample_K):
                    reward = (rs[j] - baseline) #/ std
                    selector_loss += reward * output_selector_loss[j*bsz+i]
            selector_loss = selector_loss / L 
            loss = qa_loss +  selector_loss

            
            if args.n_gpu > 1:
                loss = loss.mean()  # mean() to average on multi-gpu parallel (not distributed) trainin

            if args.gradient_accumulation_steps > 1:
                loss = loss / args.gradient_accumulation_steps

            if args.fp16:
                with amp.scale_loss(loss, optimizer) as scaled_loss:
                    scaled_loss.backward()
            else:
                loss.backward()


            # print (qa_loss.item())

            tr_loss += qa_loss.item()
            tr_selector_loss += selector_loss.item()
            if (step + 1) % args.gradient_accumulation_steps == 0:
                if args.fp16:
                    torch.nn.utils.clip_grad_norm_(amp.master_params(optimizer), args.max_grad_norm)
                else:
                    torch.nn.utils.clip_grad_norm_(model.parameters(), args.max_grad_norm)

                optimizer.step()
                scheduler.step()  # Update learning rate schedule
                model.zero_grad()
                global_step += 1
                # all_copy_rate = max(0, all_copy_rate - jianshao)

                # Log metrics
                if args.local_rank in [-1, 0] and args.logging_steps > 0 and global_step % args.logging_steps == 0:
                    # Only evaluate when single GPU otherwise metrics may not average well

                    tb_writer.add_scalar("lr", scheduler.get_lr()[0], global_step)
                    tb_writer.add_scalar("loss", (tr_loss - logging_loss) / args.logging_steps, global_step)
                    logging_loss = tr_loss

                    tb_writer.add_scalar("selector_loss", (tr_selector_loss - logging_selector_loss) / args.logging_steps, global_step)
                    logging_selector_loss = tr_selector_loss


                    tb_writer.add_scalar("dL", (tr_dL - logging_dL) / args.logging_steps, global_step)
                    logging_dL = tr_dL

                    
                if args.local_rank == -1 and (args.save_steps > 0 and global_step % args.save_steps == 0 ):
                    if  args.evaluate_during_training:
                        results = evaluate(args, model, tokenizer)
                        f1 = results['f1']
                        for key, value in results.items():
                            tb_writer.add_scalar("eval_{}".format(key), value, global_step)
                        print ('F1:', f1)

                        if f1 > best_f1:
                            print ('Best F1:', f1)
                            best_f1 = f1

                    output_dir = os.path.join(args.output_dir, "checkpoint-{}".format(global_step))
                    if not os.path.exists(output_dir):
                        os.makedirs(output_dir)
                    # Take care of distributed/parallel training
                    model_to_save = model.module if hasattr(model, "module") else model
                    model_to_save.save_pretrained(output_dir)
                    tokenizer.save_pretrained(output_dir)

                    torch.save(args, os.path.join(output_dir, "training_args.bin"))
                    logger.info("Saving model checkpoint to %s", output_dir)

                    torch.save(optimizer.state_dict(), os.path.join(output_dir, "optimizer.pt"))
                    torch.save(scheduler.state_dict(), os.path.join(output_dir, "scheduler.pt"))
                    logger.info("Saving optimizer and scheduler states to %s", output_dir)

            if args.max_steps > 0 and global_step > args.max_steps:
                epoch_iterator.close()
                break
        if args.max_steps > 0 and global_step > args.max_steps:
            train_iterator.close()
            break

    if args.local_rank in [-1, 0]:
        tb_writer.close()

    return global_step, tr_loss / global_step


def evaluate(args, model, tokenizer, prefix=""):
    dataset, examples, features = load_and_cache_examples(args, tokenizer, evaluate=True, output_examples=True)
    if not os.path.exists(args.output_dir) and args.local_rank in [-1, 0]:
        os.makedirs(args.output_dir)

    args.eval_batch_size = args.per_gpu_eval_batch_size * max(1, args.n_gpu)

    # Note that DistributedSampler samples randomly
    eval_sampler = SequentialSampler(dataset)
    eval_dataloader = DataLoader(dataset, sampler=eval_sampler, batch_size=args.eval_batch_size, num_workers=1)

    # multi-gpu evaluate
    if args.n_gpu > 1 and not isinstance(model, torch.nn.DataParallel):
        model = torch.nn.DataParallel(model)

    # Eval!
    logger.info("***** Running evaluation {} *****".format(prefix))
    logger.info("  Num examples = %d", len(dataset))
    logger.info("  Batch size = %d", args.eval_batch_size)

    all_results = []
    start_time = timeit.default_timer()

    macs_list = json.load(open('macs_list.json'))

    flops = 0
    bert_flops = 0
    distilbert_flops = 0
    try:
        layer_num = len(model.bert.encoder.layer) if hasattr(model, "bert") else len(model.module.bert.encoder.layer)
        isbert = True
    except:
        layer_num = len(model.distilbert.transformer.layer) if hasattr(model, "distilbert") else len(model.module.distilbert.transformer.layer)
        isbert = False

    for batch in tqdm(eval_dataloader, desc="Evaluating"):
        model.eval()
        batch = [t.to(args.device) for t in batch]
        L_s = batch[1].sum(dim=1)
        l = int(torch.max(L_s))
        batch[0] = batch[0][:, :l]
        batch[1] = batch[1][:, :l]
        batch[2] = batch[2][:, :l]


        with torch.no_grad():
            inputs = {
                "input_ids": batch[0],
                "attention_mask": batch[1],
                "token_type_ids": None if args.model_type in ["xlm", "roberta", "distilbert", "distilautobert"] else batch[2],
            }
            example_indices = batch[3]

            # XLNet and XLM use more arguments for their predictions
            if args.model_type in ["distilbert",  "distilautobert"]:
                inputs.pop("token_type_ids")

            outputs = model(**inputs)


        if args.model_type.find('auto')!=-1 and args.per_gpu_eval_batch_size==1:
            hidden_size = 768
            num_labels = model.num_labels if hasattr(model, "num_labels") else model.module.num_labels

            lens = outputs[2]
            outputs_probs = outputs[-1]

            times = [1, layer_num//2-1, layer_num//2] 

            while (len(lens)+1 <len(times)):
                rt = times[-1]
                times = times[:-1]
                times[-1] += rt
            for i in range(batch[0].size(0)):
                flops += macs_list[l] * times[0]
                for j in range(len(lens)):
                    lj = int(lens[j][i]*l+0.5)
                    flops += macs_list[lj] * times[j+1]
                    flops += lj * (hidden_size*32+32*1) 


                flops += hidden_size * num_labels
                bert_flops +=   macs_list[l] * layer_num + hidden_size * num_labels
                distilbert_flops +=   macs_list[l] * layer_num//2 + hidden_size * num_labels



        for i, example_index in enumerate(example_indices):
            eval_feature = features[example_index.item()]
            unique_id = int(eval_feature.unique_id)

            output = [to_list(output[i]) for output in outputs[:2]]

            # Some models (XLNet, XLM) use 5 arguments for their predictions, while the other "simpler"
            # models only use two.
            if len(output) >= 5:
                start_logits = output[0]
                start_top_index = output[1]
                end_logits = output[2]
                end_top_index = output[3]
                cls_logits = output[4]

                result = SquadResult(
                    unique_id,
                    start_logits,
                    end_logits,
                    start_top_index=start_top_index,
                    end_top_index=end_top_index,
                    cls_logits=cls_logits,
                )

            else:
                start_logits, end_logits = output
                result = SquadResult(unique_id, start_logits, end_logits)

            all_results.append(result)

    evalTime = timeit.default_timer() - start_time
    logger.info("  Evaluation done in total %f secs (%f sec per example)", evalTime, evalTime / len(dataset))
    print ('Flops:', 2 * flops / len(dataset) / 1000000.0)
    if isbert:
        print ('BERT FLOPS:', 2*bert_flops/len(dataset)/1000000.0)
        print ('DistilBERT FLOPS:', 2*distilbert_flops/len(dataset)/1000000.0)

    # Compute predictions
    output_prediction_file = os.path.join(args.output_dir, "predictions_{}.json".format(prefix))
    output_nbest_file = os.path.join(args.output_dir, "nbest_predictions_{}.json".format(prefix))

    if args.version_2_with_negative:
        output_null_log_odds_file = os.path.join(args.output_dir, "null_odds_{}.json".format(prefix))
    else:
        output_null_log_odds_file = None

    # XLNet and XLM use a more complex post-processing procedure
    if args.model_type in ["xlnet", "xlm"]:
        start_n_top = model.config.start_n_top if hasattr(model, "config") else model.module.config.start_n_top
        end_n_top = model.config.end_n_top if hasattr(model, "config") else model.module.config.end_n_top

        predictions = compute_predictions_log_probs(
            examples,
            features,
            all_results,
            args.n_best_size,
            args.max_answer_length,
            output_prediction_file,
            output_nbest_file,
            output_null_log_odds_file,
            start_n_top,
            end_n_top,
            args.version_2_with_negative,
            tokenizer,
            args.verbose_logging,
        )
    else:
        predictions = compute_predictions_logits(
            examples,
            features,
            all_results,
            args.n_best_size,
            args.max_answer_length,
            args.do_lower_case,
            output_prediction_file,
            output_nbest_file,
            output_null_log_odds_file,
            args.verbose_logging,
            args.version_2_with_negative,
            args.null_score_diff_threshold,
            tokenizer,
        )

    # Compute the F1 and exact scores.
    results = squad_evaluate(examples, predictions)
    results['FLOPS'] = 2*flops/len(dataset)/1000000.0
    # print (results)
    return results



def train_init(args, train_dataset, model, tokenizer):
    """ Train the model """
    if args.local_rank in [-1, 0]:
        tb_writer = SummaryWriter("logs/squad2_log/" + args.output_dir[args.output_dir.find('/')+1:])

    args.train_batch_size = args.per_gpu_train_batch_size * max(1, args.n_gpu)

    train_sampler = RandomSampler(train_dataset) if args.local_rank == -1 else DistributedSampler(train_dataset)

    train_dataloader = DataLoader(train_dataset, sampler=train_sampler, batch_size=args.train_batch_size, num_workers=1)

    if args.max_steps > 0:
        t_total = args.max_steps
        args.num_train_epochs = args.max_steps // (len(train_dataloader) // args.gradient_accumulation_steps) + 1
    else:
        t_total = len(train_dataloader) // args.gradient_accumulation_steps * args.num_train_epochs



    train_params = []
    for n, p in model.named_parameters():        
        # if n.find('bert.encoder.linear_1.3')!=-1 or n.find('bert.encoder.linear_2.3')!=-1:
        if n.find('linear_1')!=-1 or n.find('linear_2')!=-1 or n.find('linear_3')!=-1 \
            or n.find('linear_4')!=-1 or n.find('linear_5')!=-1 \
                or n.find('linear_6')!=-1 or n.find('linear_7')!=-1  \
                    or n.find('linear_7')!=-1 or n.find('linear_8')!=-1 :
            train_params.append((n, p))
            print (n)
        else:
            p.requires_grad = False
    no_decay = ["bias", "LayerNorm.weight"]
    optimizer_grouped_parameters = [
        {
            "params": [p for n, p in train_params if not any(nd in n for nd in no_decay)],
            "weight_decay": args.weight_decay,
        },
        {"params": [p for n, p in train_params if any(nd in n for nd in no_decay)], "weight_decay": 0.0},
    ]
    optimizer = AdamW(optimizer_grouped_parameters, lr=args.learning_rate, eps=args.adam_epsilon)
    if args.warmup_steps==-1:
        args.warmup_steps = int(t_total*0.1)
    scheduler = get_linear_schedule_with_warmup(
        optimizer, num_warmup_steps=args.warmup_steps, num_training_steps=t_total
    )


    if args.fp16:
        try:
            from apex import amp
        except ImportError:
            raise ImportError("Please install apex from https://www.github.com/nvidia/apex to use fp16 training.")

        model, optimizer = amp.initialize(model, optimizer, opt_level=args.fp16_opt_level)

    # multi-gpu training (should be after apex fp16 initialization)
    if args.n_gpu > 1:
        model = torch.nn.DataParallel(model)

    # Distributed training (should be after apex fp16 initialization)
    if args.local_rank != -1:
        model = torch.nn.parallel.DistributedDataParallel(
            model, device_ids=[args.local_rank], output_device=args.local_rank, find_unused_parameters=True
        )

    # Train!
    logger.info("***** Running training *****")
    logger.info("  Num examples = %d", len(train_dataset))
    logger.info("  Num Epochs = %d", args.num_train_epochs)
    logger.info("  Instantaneous batch size per GPU = %d", args.per_gpu_train_batch_size)
    logger.info(
        "  Total train batch size (w. parallel, distributed & accumulation) = %d",
        args.train_batch_size
        * args.gradient_accumulation_steps
        * (torch.distributed.get_world_size() if args.local_rank != -1 else 1),
    )
    logger.info("  Gradient Accumulation steps = %d", args.gradient_accumulation_steps)
    logger.info("  Total optimization steps = %d", t_total)

    global_step = 0
    epochs_trained = 0

    tr_loss, logging_loss = 0.0, 0.0


    model.zero_grad()
    train_iterator = trange(
        epochs_trained, int(args.num_train_epochs), desc="Epoch", disable=args.local_rank not in [-1, 0]
    )
    # Added here for reproductibility
    set_seed(args)

    for _ in train_iterator:
        epoch_iterator = tqdm(train_dataloader, desc="Iteration", disable=args.local_rank not in [-1, 0])
        for step, batch in enumerate(epoch_iterator):


            model.train()
            batch = tuple(t.to(args.device) for t in batch)

            inputs = {
                "input_ids": batch[0],
                "attention_mask": batch[1],
                "rank_prob": batch[-1]
            }


            outputs = model(**inputs)
            loss = outputs[0]

            if args.n_gpu > 1:
                loss = loss.mean()  # mean() to average on multi-gpu parallel (not distributed) training


            if args.gradient_accumulation_steps > 1:
                loss = loss / args.gradient_accumulation_steps

            if args.fp16:
                with amp.scale_loss(loss, optimizer) as scaled_loss:
                    scaled_loss.backward()
            else:
                loss.backward()

            tr_loss += loss.item()
            if (step + 1) % args.gradient_accumulation_steps == 0:
                if args.fp16:
                    torch.nn.utils.clip_grad_norm_(amp.master_params(optimizer), args.max_grad_norm)
                else:
                    torch.nn.utils.clip_grad_norm_(model.parameters(), args.max_grad_norm)

                optimizer.step()
                scheduler.step()  # Update learning rate schedule
                model.zero_grad()
                global_step += 1

                # Log metrics
                if args.local_rank in [-1, 0] and args.logging_steps > 0 and global_step % args.logging_steps == 0:
                    # Only evaluate when single GPU otherwise metrics may not average well

                    tb_writer.add_scalar("lr", scheduler.get_lr()[0], global_step)
                    tb_writer.add_scalar("loss", (tr_loss - logging_loss) / args.logging_steps, global_step)
                    logging_loss = tr_loss


            if args.max_steps > 0 and global_step > args.max_steps:
                epoch_iterator.close()
                break
        if args.max_steps > 0 and global_step > args.max_steps:
            train_iterator.close()
            break

    if args.local_rank in [-1, 0]:
        tb_writer.close()

    return global_step, tr_loss / global_step

def main():
    parser = argparse.ArgumentParser()

    # Required parameters
    parser.add_argument(
        "--model_type",
        default=None,
        type=str,
        required=True,
        help="Model type selected in the list: " + ", ".join(MODEL_CLASSES.keys()),
    )
    parser.add_argument(
        "--model_name_or_path",
        default=None,
        type=str,
        required=True,
        help="Path to pre-trained model or shortcut name selected in the list: " + ", ".join(ALL_MODELS),
    )
    parser.add_argument(
        "--output_dir",
        default=None,
        type=str,
        required=True,
        help="The output directory where the model checkpoints and predictions will be written.",
    )

    # Other parameters
    parser.add_argument(
        "--data_dir",
        default=None,
        type=str,
        help="The input data dir. Should contain the .json files for the task."
        + "If no data dir or train/predict files are specified, will run with tensorflow_datasets.",
    )
    parser.add_argument(
        "--train_file",
        default="train-v2.0.json",
        type=str,
        help="The input training file. If a data dir is specified, will look for the file there"
        + "If no data dir or train/predict files are specified, will run with tensorflow_datasets.",
    )
    parser.add_argument(
        "--predict_file",
        default="dev-v2.0.json",
        type=str,
        help="The input evaluation file. If a data dir is specified, will look for the file there"
        + "If no data dir or train/predict files are specified, will run with tensorflow_datasets.",
    )
    parser.add_argument(
        "--config_name", default="", type=str, help="Pretrained config name or path if not the same as model_name"
    )
    parser.add_argument(
        "--tokenizer_name",
        default="",
        type=str,
        help="Pretrained tokenizer name or path if not the same as model_name",
    )
    parser.add_argument(
        "--cache_dir",
        default="",
        type=str,
        help="Where do you want to store the pre-trained models downloaded from s3",
    )

    parser.add_argument(
        "--version_2_with_negative",
        action="store_true",
        help="If true, the SQuAD examples contain some that do not have an answer.",
    )
    parser.add_argument(
        "--null_score_diff_threshold",
        type=float,
        default=0.0,
        help="If null_score - best_non_null is greater than the threshold predict null.",
    )

    parser.add_argument(
        "--max_seq_length",
        default=384,
        type=int,
        help="The maximum total input sequence length after WordPiece tokenization. Sequences "
        "longer than this will be truncated, and sequences shorter than this will be padded.",
    )
    parser.add_argument(
        "--doc_stride",
        default=128,
        type=int,
        help="When splitting up a long document into chunks, how much stride to take between chunks.",
    )
    parser.add_argument(
        "--max_query_length",
        default=64,
        type=int,
        help="The maximum number of tokens for the question. Questions longer than this will "
        "be truncated to this length.",
    )
    parser.add_argument("--do_train", action="store_true", help="Whether to run training.")
    parser.add_argument("--do_eval", action="store_true", help="Whether to run eval on the dev set.")
    parser.add_argument(
        "--evaluate_during_training", action="store_true", help="Rul evaluation during training at each logging step."
    )
    parser.add_argument(
        "--do_lower_case", action="store_true", help="Set this flag if you are using an uncased model."
    )

    parser.add_argument("--per_gpu_train_batch_size", default=8, type=int, help="Batch size per GPU/CPU for training.")
    parser.add_argument(
        "--per_gpu_eval_batch_size", default=8, type=int, help="Batch size per GPU/CPU for evaluation."
    )
    parser.add_argument("--learning_rate", default=5e-5, type=float, help="The initial learning rate for Adam.")
    parser.add_argument(
        "--gradient_accumulation_steps",
        type=int,
        default=1,
        help="Number of updates steps to accumulate before performing a backward/update pass.",
    )
    parser.add_argument("--weight_decay", default=0.0, type=float, help="Weight decay if we apply some.")
    parser.add_argument("--adam_epsilon", default=1e-8, type=float, help="Epsilon for Adam optimizer.")
    parser.add_argument("--max_grad_norm", default=1.0, type=float, help="Max gradient norm.")
    parser.add_argument(
        "--num_train_epochs", default=3.0, type=float, help="Total number of training epochs to perform."
    )
    parser.add_argument(
        "--max_steps",
        default=-1,
        type=int,
        help="If > 0: set total number of training steps to perform. Override num_train_epochs.",
    )
    parser.add_argument("--warmup_steps", default=-1, type=int, help="Linear warmup over warmup_steps.")
    parser.add_argument(
        "--n_best_size",
        default=20,
        type=int,
        help="The total number of n-best predictions to generate in the nbest_predictions.json output file.",
    )
    parser.add_argument(
        "--max_answer_length",
        default=30,
        type=int,
        help="The maximum length of an answer that can be generated. This is needed because the start "
        "and end predictions are not conditioned on one another.",
    )
    parser.add_argument(
        "--verbose_logging",
        action="store_true",
        help="If true, all of the warnings related to data processing will be printed. "
        "A number of warnings are expected for a normal SQuAD evaluation.",
    )

    parser.add_argument("--train_rl",
                        default=False,
                        action='store_true',
                        help=" ")

    parser.add_argument("--logging_steps", type=int, default=5, help="Log every X updates steps.")
    parser.add_argument("--save_steps", type=int, default=100000, help="Save checkpoint every X updates steps.")
    parser.add_argument(
        "--eval_all_checkpoints",
        action="store_true",
        help="Evaluate all checkpoints starting with the same prefix as model_name ending and ending with step number",
    )
    parser.add_argument("--no_cuda", action="store_true", help="Whether not to use CUDA when available")
    parser.add_argument(
        "--overwrite_output_dir", action="store_true", help="Overwrite the content of the output directory"
    )
    parser.add_argument(
        "--overwrite_cache", action="store_true", help="Overwrite the cached training and evaluation sets"
    )
    parser.add_argument("--seed", type=int, default=42, help="random seed for initialization")

    parser.add_argument("--local_rank", type=int, default=-1, help="local_rank for distributed training on gpus")
    parser.add_argument(
        "--fp16",
        action="store_true",
        help="Whether to use 16-bit (mixed) precision (through NVIDIA apex) instead of 32-bit",
    )
    parser.add_argument(
        "--fp16_opt_level",
        type=str,
        default="O1",
        help="For fp16: Apex AMP optimization level selected in ['O0', 'O1', 'O2', and 'O3']."
        "See details at https://nvidia.github.io/apex/amp.html",
    )
    parser.add_argument("--server_ip", type=str, default="", help="Can be used for distant debugging.")
    parser.add_argument("--server_port", type=str, default="", help="Can be used for distant debugging.")

    parser.add_argument("--threads", type=int, default=1, help="multiple threads for converting example to features")

    parser.add_argument("--do_eval_grad",
                        default=False,
                        action='store_true',
                        help="Whether to run eval on the dev set.")

    parser.add_argument("--do_eval_logits",
                        default=False,
                        action='store_true',
                        help="Whether to run eval on the dev set.")


    parser.add_argument("--train_both",
                        default=False,
                        action='store_true',
                        help=" ")

    parser.add_argument("--alpha", default=1.0, type=float, help="")

    parser.add_argument("--guide_rate", default=0.2, type=float, help="")

    parser.add_argument("--train_init",
                        default=False,
                        action='store_true',
                        help=" ")

    parser.add_argument("--train_teacher",
                        default=False,
                        action='store_true',
                        help=" ")

    parser.add_argument("--teacher_npy_path",
                        default="npy_folder/squad_logits.npy",
                        type=str,
                        required=False)

    args = parser.parse_args()

    if (
        os.path.exists(args.output_dir)
        and os.listdir(args.output_dir)
        and args.do_train
        and not args.overwrite_output_dir
    ):
        raise ValueError(
            "Output directory ({}) already exists and is not empty. Use --overwrite_output_dir to overcome.".format(
                args.output_dir
            )
        )
    def create_exp_dir(path, scripts_to_save=None):
        if args.output_dir.endswith("test"):
            return
        if not os.path.exists(path):
            os.mkdir(path)

        print('Experiment dir : {}'.format(path))
        if scripts_to_save is not None:
            if not os.path.exists(os.path.join(path, 'scripts')):
                os.mkdir(os.path.join(path, 'scripts'))
            for script in scripts_to_save:
                dst_file = os.path.join(path, 'scripts', os.path.basename(script))
                shutil.copyfile(script, dst_file)

    if args.do_train and args.local_rank in [-1, 0] and args.output_dir.find('test')==-1:
        create_exp_dir(args.output_dir, scripts_to_save=['run_squad.py',  
        'transformers/src/transformers/modeling_distilautoqabert.py', 'transformers/src/transformers/modeling_autoqabert.py',])

    # Setup distant debugging if needed
    if args.server_ip and args.server_port:
        # Distant debugging - see https://code.visualstudio.com/docs/python/debugging#_attach-to-a-local-script
        import ptvsd

        print("Waiting for debugger attach")
        ptvsd.enable_attach(address=(args.server_ip, args.server_port), redirect_output=True)
        ptvsd.wait_for_attach()

    # Setup CUDA, GPU & distributed training
    if args.local_rank == -1 or args.no_cuda:
        device = torch.device("cuda" if torch.cuda.is_available() and not args.no_cuda else "cpu")
        args.n_gpu = torch.cuda.device_count()
    else:  # Initializes the distributed backend which will take care of sychronizing nodes/GPUs
        torch.cuda.set_device(args.local_rank)
        device = torch.device("cuda", args.local_rank)
        torch.distributed.init_process_group(backend="nccl")
        args.n_gpu = 1
    args.device = device

    # Setup logging
    logging.basicConfig(
        format="%(asctime)s - %(levelname)s - %(name)s -   %(message)s",
        datefmt="%m/%d/%Y %H:%M:%S",
        level=logging.INFO if args.local_rank in [-1, 0] else logging.WARN,
    )
    logger.warning(
        "Process rank: %s, device: %s, n_gpu: %s, distributed training: %s, 16-bits training: %s",
        args.local_rank,
        device,
        args.n_gpu,
        bool(args.local_rank != -1),
        args.fp16,
    )

    # Set seed
    set_seed(args)

    # Load pretrained model and tokenizer
    if args.local_rank not in [-1, 0]:
        # Make sure only the first process in distributed training will download model & vocab
        torch.distributed.barrier()

    args.model_type = args.model_type.lower()
    config_class, model_class, tokenizer_class = MODEL_CLASSES[args.model_type]
    config = config_class.from_pretrained(
        args.config_name if args.config_name else args.model_name_or_path,
        cache_dir=args.cache_dir if args.cache_dir else None,
    )
    if args.do_eval_grad:
        config.output_hidden_states = True
    tokenizer = tokenizer_class.from_pretrained(
        args.tokenizer_name if args.tokenizer_name else args.model_name_or_path,
        do_lower_case=args.do_lower_case,
        cache_dir=args.cache_dir if args.cache_dir else None,
    )
    model = model_class.from_pretrained(
        args.model_name_or_path,
        from_tf=bool(".ckpt" in args.model_name_or_path),
        config=config,
        cache_dir=args.cache_dir if args.cache_dir else None,
    )

    if args.local_rank == 0:
        # Make sure only the first process in distributed training will download model & vocab
        torch.distributed.barrier()

    model.to(args.device)

    logger.info("Training/evaluation parameters %s", args)

    # Before we do anything with models, we want to ensure that we get fp16 execution of torch.einsum if args.fp16 is set.
    # Otherwise it'll default to "promote" mode, and we'll get fp32 operations. Note that running `--fp16_opt_level="O2"` will
    # remove the need for this code, but it is still valid.
    if args.fp16:
        try:
            import apex

            apex.amp.register_half_function(torch, "einsum")
        except ImportError:
            raise ImportError("Please install apex from https://www.github.com/nvidia/apex to use fp16 training.")

    # Training
    if args.do_train:
        if args.train_rl:
            train_dataset = load_and_cache_examples(args, tokenizer, evaluate=False, output_examples=False)
            global_step, tr_loss = train_rl(args, train_dataset, model, tokenizer)
        elif args.train_both:
            train_dataset = load_and_cache_examples(args, tokenizer, evaluate=False, output_examples=False)
            global_step, tr_loss = train_both(args, train_dataset, model, tokenizer)
        elif args.train_init:
            train_dataset = load_and_cache_examples(args, tokenizer, evaluate=False, output_examples=False)
            global_step, tr_loss = train_init(args, train_dataset, model, tokenizer)
        else:
            train_dataset = load_and_cache_examples(args, tokenizer, evaluate=False, output_examples=False)
            global_step, tr_loss = train(args, train_dataset, model, tokenizer)
        logger.info(" global_step = %s, average loss = %s", global_step, tr_loss)

    # Save the trained model and the tokenizer
    if args.do_train and (args.local_rank == -1 or torch.distributed.get_rank() == 0):
        # Create output directory if needed
        if not os.path.exists(args.output_dir) and args.local_rank in [-1, 0]:
            os.makedirs(args.output_dir)

        logger.info("Saving model checkpoint to %s", args.output_dir)
        # Save a trained model, configuration and tokenizer using `save_pretrained()`.
        # They can then be reloaded using `from_pretrained()`
        # Take care of distributed/parallel training
        model_to_save = model.module if hasattr(model, "module") else model
        model_to_save.save_pretrained(args.output_dir)
        tokenizer.save_pretrained(args.output_dir)

        # Good practice: save your training arguments together with the trained model
        torch.save(args, os.path.join(args.output_dir, "training_args.bin"))

        # Load a trained model and vocabulary that you have fine-tuned
        model = model_class.from_pretrained(args.output_dir, force_download=True)
        tokenizer = tokenizer_class.from_pretrained(args.output_dir, do_lower_case=args.do_lower_case)
        model.to(args.device)

    # Evaluation - we can ask to evaluate all the checkpoints (sub-directories) in a directory
    results = {}
    if args.do_eval and args.local_rank in [-1, 0]:
        # if args.do_train:
        #     logger.info("Loading checkpoints saved during training for evaluation")
        #     checkpoints = [args.output_dir]
        if args.eval_all_checkpoints:
            checkpoints = list(
                os.path.dirname(c)
                for c in sorted(glob.glob(args.output_dir + "/**/" + WEIGHTS_NAME, recursive=True))
            )
            logging.getLogger("transformers.modeling_utils").setLevel(logging.WARN)  # Reduce model loading logs
        else:
            logger.info("Loading checkpoints saved during training for evaluation")
            checkpoints = [args.output_dir]

            # logger.info("Loading checkpoint %s for evaluation", args.model_name_or_path)
            # checkpoints = [args.model_name_or_path]

        logger.info("Evaluate the following checkpoints: %s", checkpoints)

        for checkpoint in checkpoints:
            # Reload the model
            global_step = checkpoint.split("-")[-1] if len(checkpoints) > 1 else ""
            model = model_class.from_pretrained(checkpoint, force_download=True)
            model.to(args.device)

            # Evaluate
            result = evaluate(args, model, tokenizer, prefix=global_step)

            result = dict((k + ("_{}".format(global_step) if global_step else ""), v) for k, v in result.items())
            results.update(result)

    logger.info("Results: {}".format(results))

    if args.do_eval_grad and args.local_rank in [-1, 0]:
        
        checkpoints = [args.output_dir]
        logger.info("Evaluate the following checkpoints: %s", checkpoints)

        for checkpoint in checkpoints:
            # Reload the model
            global_step = checkpoint.split("-")[-1] if len(checkpoints) > 1 else ""
            model = model_class.from_pretrained(checkpoint, force_download=True, config=config)
            model.to(args.device)

            # Evaluate
            result = evaluate_grad(args, model, tokenizer, prefix=global_step, evaluate=False)

            result = dict((k + ("_{}".format(global_step) if global_step else ""), v) for k, v in result.items())
            results.update(result)

    if args.do_eval_logits and args.local_rank in [-1, 0]:

        checkpoints = [args.output_dir]
        logger.info("Evaluate the following checkpoints: %s", checkpoints)

        for checkpoint in checkpoints:
            # Reload the model
            global_step = checkpoint.split("-")[-1] if len(checkpoints) > 1 else ""
            model = model_class.from_pretrained(checkpoint, force_download=True, config=config)
            model.to(args.device)

            # Evaluate
            result = evaluate_logits(args, model, tokenizer, prefix=global_step, evaluate=False)

            result = dict((k + ("_{}".format(global_step) if global_step else ""), v) for k, v in result.items())
            results.update(result)


    return results


if __name__ == "__main__":
    main()