FnRunnerTest with non-trivial (order 1000 elements) numpy input flakes in non-cython environment

 apache_beam/runners/portability/fn_api_runner/fn_runner_test.py:141: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
apache_beam/pipeline.py:596: in __exit__
    self.result = self.run()
apache_beam/pipeline.py:573: in run
    return self.runner.run_pipeline(self, self._options)
apache_beam/runners/portability/fn_api_runner/fn_runner.py:200: in run_pipeline
    pipeline.to_runner_api(default_environment=self._default_environment))
apache_beam/runners/portability/fn_api_runner/fn_runner.py:208: in run_via_runner_api
    return self.run_stages(stage_context, stages)
apache_beam/runners/portability/fn_api_runner/fn_runner.py:409: in run_stages
    runner_execution_context, bundle_context_manager, bundle_input)
apache_beam/runners/portability/fn_api_runner/fn_runner.py:742: in _execute_bundle
    bundle_manager))
apache_beam/runners/portability/fn_api_runner/fn_runner.py:966: in _run_bundle
    data_input, data_output, input_timers, expected_timer_output)
apache_beam/runners/portability/fn_api_runner/fn_runner.py:1309: in process_bundle
    output.transform_id).append(output.data)
apache_beam/runners/portability/fn_api_runner/execution.py:242: in append
    windowed_key_value = coder_impl.decode_from_stream(input_stream, True)
apache_beam/coders/coder_impl.py:1446: in decode_from_stream
    value = self._value_coder.decode_from_stream(in_stream, nested)
apache_beam/coders/coder_impl.py:994: in decode_from_stream
    c in enumerate(self._coder_impls)
apache_beam/coders/coder_impl.py:994: in <listcomp>
    c in enumerate(self._coder_impls)
apache_beam/coders/coder_impl.py:617: in decode_from_stream
    return in_stream.read_all(nested)
apache_beam/coders/slow_stream.py:137: in read_all
    return self.read(self.read_var_int64() if nested else self.size())
apache_beam/coders/slow_stream.py:148: in read_var_int64
    byte = self.read_byte()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ self = <apache_beam.coders.slow_stream.InputStream object at 0x7f8433d63190>    def read_byte(self):
      # type: () -> int
      self.pos += 1
>     return self.data[self.pos - 1]
E     IndexError: index out of rangeapache_beam/coders/slow_stream.py:142: IndexError