Override existing hyperparameter values, parsing new values from a dictionary.

    Args:
      values_dict: Dictionary of name:value pairs.

    Returns:
      The `HParams` instance.

    Raises:
      KeyError: If a hyperparameter in `values_dict` doesn't exist.
      ValueError: If `values_dict` cannot be parsed.

def override_from_dict(self, values_dict):
    """Override existing hyperparameter values, parsing new values from a dictionary.

    Args:
      values_dict: Dictionary of name:value pairs.

    Returns:
      The `HParams` instance.

    Raises:
      KeyError: If a hyperparameter in `values_dict` doesn't exist.
      ValueError: If `values_dict` cannot be parsed.
    """
    for name, value in values_dict.items():
      self.set_hparam(name, value)
    return self