def WhichOneof(self, oneof_group):
    'Returns the name of the field that is set inside a oneof group.\n\n    If no field is set, returns None.\n\n    Args:\n      oneof_group (str): the name of the oneof group to check.\n\n    Returns:\n      str or None: The name of the group that is set, or None.\n\n    Raises:\n      ValueError: no group with the given name exists\n    '
    raise NotImplementedError
Returns the name of the field that is set inside a oneof group.

If no field is set, returns None.

Args:
  oneof_group (str): the name of the oneof group to check.

Returns:
  str or None: The name of the group that is set, or None.

Raises:
  ValueError: no group with the given name exists
def WhichOneof(self, oneof_group):
    'Returns the name of the field that is set inside a oneof group.\n\n    If no field is set, returns None.\n\n    Args:\n      oneof_group (str): the name of the oneof group to check.\n\n    Returns:\n      str or None: The name of the group that is set, or None.\n\n    Raises:\n      ValueError: no group with the given name exists\n    '
    raise NotImplementedError