TypeHints Py3 Error: Multiple tests fail with a generator StopIteration error on Python 3.7

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ERROR: test_top_of_runtime_checking_satisfied (apache_beam.transforms.ptransform_test.PTransformTypeCheckTestCase)
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Traceback (most recent call last):
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/transforms/ptransform_test.py", line 1900, in test_top_of_runtime_checking_satisfied
    self.p.run()
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/testing/test_pipeline.py", line 107, in run
    else test_runner_api))
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/pipeline.py", line 419, in run
    return self.runner.run_pipeline(self, self._options)
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/direct/direct_runner.py", line 132, in run_pipeline
    return runner.run_pipeline(pipeline, options)
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/portability/fn_api_runner.py", line 276, in run_pipeline
    default_environment=self._default_environment))
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/portability/fn_api_runner.py", line 280, in run_via_runner_api
    return self.run_stages(*self.create_stages(pipeline_proto))
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/portability/fn_api_runner.py", line 356, in run_stages
    stage_context.safe_coders)
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/portability/fn_api_runner.py", line 511, in run_stage
    data_input, data_output)
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/portability/fn_api_runner.py", line 1217, in process_bundle
    result_future = self._controller.control_handler.push(process_bundle)
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/portability/fn_api_runner.py", line 832, in push
    response = self.worker.do_instruction(request)
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/worker/sdk_worker.py", line 312, in do_instruction
    request.instruction_id)
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/worker/sdk_worker.py", line 331, in process_bundle
    bundle_processor.process_bundle(instruction_id))
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/worker/bundle_processor.py", line 559, in process_bundle
    op.finish()
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/worker/operations.py", line 580, in finish
    self.dofn_runner.finish()
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/common.py", line 781, in finish
    self._invoke_bundle_method(self.do_fn_invoker.invoke_finish_bundle)
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/common.py", line 775, in _invoke_bundle_method
    self._reraise_augmented(exn)
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/common.py", line 800, in _reraise_augmented
    raise_with_traceback(new_exn)
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/target/.tox-py37/py37/lib/python3.7/site-packages/future/utils/__init__.py", line 419, in raise_with_traceback
    raise exc.with_traceback(traceback)
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/common.py", line 773, in _invoke_bundle_method
    bundle_method()
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/common.py", line 369, in invoke_finish_bundle
    self.signature.finish_bundle_method.method_value())
  File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/runners/common.py", line 895, in finish_bundle_outputs
    for result in results:
RuntimeError: generator raised StopIteration [while running 'AciiTop/ParDo(_TopPerBundle)']

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 ERROR: test_functions_as_regular_generator (apache_beam.typehints.typehints_test.TestGeneratorWrapper)
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 Traceback (most recent call last):
 File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/typehints/decorators.py", line 612, in _iter_
 x = next(self.internal_gen)
 StopIteration
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
 File "/home/jenkins/jenkins-slave/workspace/beam_PreCommit_Python_Commit/src/sdks/python/test-suites/tox/py37/build/srcs/sdks/python/apache_beam/typehints/typehints_test.py", line 725, in test_functions_as_regular_generator
 self.assertEqual((1, 2, 3), tuple(wrapped_gen))
 RuntimeError: generator raised StopIteration