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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 _create_hparam_extractor(hparam_name):
 """Returns an extractor function that extracts an hparam from a session group. Args: hparam_name: str. Identies the hparam to extract from the session group. Returns: A function that takes a tensorboard.hparams.SessionGroup protobuffer and returns the value, as a native Python object, of the hparam identified by 'hparam_name'. """

  def extractor_fn(session_group):
    if hparam_name in session_group.hparams:
      return _value_to_python(session_group.hparams[hparam_name])
    return None

  return extractor_fn