XLnet colab example error .

[AlexTrinityBlock]

When I run XLnet colab example

https://github.com/zihangdai/xlnet/blob/master/notebooks/colab_imdb_gpu.ipynb

It showed the following error:

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Traceback (most recent call last):
File "xlnet/run_classifier.py", line 25, in
import model_utils
File "/content/xlnet/model_utils.py", line 295, in
class AdamWeightDecayOptimizer(tf.train.Optimizer):
AttributeError: module 'tensorflow._api.v2.train' has no attribute 'Optimizer'

[AlexTrinityBlock]

Is Tensorflow 1. x no longer supported on google colab ?

What should I do ?

If it's need conda for support Tensorflow 1. x , please tell me how to do that I can't finish it myself.