Factory for getting a list of TensorFlow hooks for training by name.

  Args:
    name_list: a list of strings to name desired hook classes. Allowed:
      LoggingTensorHook, ProfilerHook, ExamplesPerSecondHook, which are defined
      as keys in HOOKS
    **kwargs: a dictionary of arguments to the hooks.

  Returns:
    list of instantiated hooks, ready to be used in a classifier.train call.

  Raises:
    ValueError: if an unrecognized name is passed.

def get_train_hooks(name_list, **kwargs):
  """Factory for getting a list of TensorFlow hooks for training by name.

  Args:
    name_list: a list of strings to name desired hook classes. Allowed:
      LoggingTensorHook, ProfilerHook, ExamplesPerSecondHook, which are defined
      as keys in HOOKS
    **kwargs: a dictionary of arguments to the hooks.

  Returns:
    list of instantiated hooks, ready to be used in a classifier.train call.

  Raises:
    ValueError: if an unrecognized name is passed.
  """

  if not name_list:
    return []

  train_hooks = []
  for name in name_list:
    hook_name = HOOKS.get(name.strip().lower())
    if hook_name is None:
      raise ValueError('Unrecognized training hook requested: {}'.format(name))
    else:
      train_hooks.append(hook_name(**kwargs))

  return train_hooks