code: def _rectify(settings):
      
      for key, rectifier in _settings_rectifiers.items():
          try:
              new_value = rectifier['func'](settings[key])
              if new_value is False:
                  raise AuthzConfigurationError(
                      'Error validating {}->{}: {}'.format(
                          _settings_key, key, rectifier['errmsg']))
              settings[key] = new_value
          except:
              raise AuthzConfigurationError(
                  'Error validating {}->{}: {}'.format(
                      _settings_key, key, rectifier['errmsg']))
docs: Rectify (and validate) the given settings using the functions in
      :data:`_settings_rectifiers`.