message: Mention in basic_session_run_hooks' docstrings that the symbol is also exported to v2 tf.estimator namespace.
diff: # See the License for the specific language governing permissions and
  # limitations under the License.
  # ==============================================================================
  -"""Some common SessionRunHook classes."""
  +"""Some common SessionRunHook classes.
  +
  +Note that the symbols that are exported to v1 tf.train namespace are also
  +exported to v2 in tf.estimator namespace. See
  +https://github.com/tensorflow/estimator/blob/master/tensorflow_estimator/python/estimator/hooks/basic_session_run_hooks.py
  +"""
  from __future__ import absolute_import
  from __future__ import division
  @@ -84,7 +89,11 @@ class _HookTimer(object):
  @tf_export(v1=["train.SecondOrStepTimer"])
  class SecondOrStepTimer(_HookTimer):
  - """Timer that triggers at most once every N seconds or once every N steps."""
  + """Timer that triggers at most once every N seconds or once every N steps.
  +
  + This symbol is also exported to v2 in tf.estimator namespace. See
  + https://github.com/tensorflow/estimator/blob/master/tensorflow_estimator/python/estimator/hooks/basic_session_run_hooks.py
  + """
  def __init__(self, every_secs=None, every_steps=None):
  self.reset()
  