code: def _validate_calibration_params(strategy='accuracy', min_rate=None,
                                     beta=1.):
      
      if strategy not in ('accuracy', 'f_beta', 'max_tpr',
                          'max_tnr'):
        raise ValueError('Strategy can either be "accuracy", "f_beta" or '
                         '"max_tpr" or "max_tnr". Got "{}" instead.'
                         .format(strategy))
      if strategy == 'max_tpr' or strategy == 'max_tnr':
        if (min_rate is None or not isinstance(min_rate, (int, float)) or
                not min_rate >= 0 or not min_rate <= 1):
          raise ValueError('Parameter min_rate must be a number in'
                           '[0, 1]. '
                           'Got {} instead.'.format(min_rate))
      if strategy == 'f_beta':
        if beta is None or not isinstance(beta, (int, float)):
          raise ValueError('Parameter beta must be a real number. '
                           'Got {} instead.'.format(type(beta)))
docs: Ensure that calibration parameters have allowed values