message: Add PYTHONPATH to bazelrc when necessary
  When the user choosen python_lib_path was retreived from the
  PYTHONPATH environment variable, need to set PYTHONPATH in the
  bazelrc file so bazel includes it in all the build operations.
  Fixes tensorflow#23695
diff: @@ -238,6 +238,13 @@ def setup_python(environ_cp):
  write_to_bazelrc('build --python_path=\"%s"' % python_bin_path)
  environ_cp['PYTHON_BIN_PATH'] = python_bin_path
  + # If choosen python_lib_path is from a path specified in the PYTHONPATH
  + # variable, need to tell bazel to include PYTHONPATH
  + if environ_cp.get('PYTHONPATH'):
  + python_paths = environ_cp.get('PYTHONPATH').split(':')
  + if python_lib_path in python_paths:
  + write_action_env_to_bazelrc('PYTHONPATH', environ_cp.get('PYTHONPATH'))
  +
  # Write tools/python_bin_path.sh
  with open(
  os.path.join(_TF_WORKSPACE_ROOT, 'tools', 'python_bin_path.sh'),
  