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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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