code: def hash(self):
          '''
          :rtype: int
          :return: hash of the field
          '''
          hashed = super(Group, self).hash()
          return khash(hashed, frozenset(self._values)f hash(self):
          '''
          :rtype: int
          :return: hash of the field
          '''
          hashed = super(Group, self).hash()
          return khash(hashed, frozenset(self._values))
docs: :rtype: int
          :return: hash of the field