code: def get(self, key, default=_sentinel):
          
          if default is _sentinel:
              default = HyperParams({})
          return self.__dict__[key] if key in self.__dict__ else default
docs: Get the value specified in the dictionary or a default.
          :param key: The key which should be retrieved.
          :param default: The default that is returned if the key is not set.
          :return: The value from the dict or the default.