fix: add get_run function to Python SDK (#162)

templates/python/__init__package.handlebars

@@ -31,7 +31,7 @@ __import__('sys').setrecursionlimit({{recursionLimit}})
 
 from {{packageName}}.providers.evaluation import *
 from {{packageName}}.providers.pipeline import Pipeline
-from {{packageName}}.providers.pipeline_run import PipelineRun, flush
+from {{packageName}}.providers.pipeline_run import PipelineRun, flush, get_run
 from {{packageName}}.providers.step_run import StepRun
 from {{packageName}}.providers.utils import to_date_string
 from {{packageName}}.providers.files import *