docs: def meta_data_hash(self, obj_hash=None):
          """Creates a hash with the meta data of the model
  
          :param obj_hash: The hash object (see Python hashlib)
          :return: The updated hash object
          """
          if obj_hash is None:
              obj_hash = hashlib.sha256()
          self.update_meta_data_hash(obj_hash)
          return obj_hash