message: Fix estimator import in tensorflow.compat.v1 module.
diff: @@ -28,7 +28,8 @@ from tensorflow.python import pywrap_tensorflow # pylint: disable=unused-import
  from tensorflow.python.tools import component_api_helper as _component_api_helper
  _component_api_helper.package_hook(
  parent_package_str=__name__,
  - child_package_str=('tensorflow_estimator.python.estimator.api.estimator'))
  + child_package_str=(
  + 'tensorflow_estimator.python.estimator.api._v1.estimator'))
  _component_api_helper.package_hook(
  parent_package_str=__name__,
  child_package_str=('tensorflow.python.keras.api._v1.keras'))
  