code: def _GetMessageFromFactory(factory, full_name):
    
    proto_descriptor = factory.pool.FindMessageTypeByName(full_name)
    proto_cls = factory.GetPrototype(proto_descriptor)
    return proto_cls
docs: Get a proto class from the MessageFactory by name.
  
    Args:
      factory: a MessageFactory instance.
      full_name: str, the fully qualified name of the proto type.
    Returns:
      A class, for the type identified by full_name.
    Raises:
      KeyError, if the proto is not found in the factory's descriptor pool.