docs: def certify_enum_value(value, kind=None, required=True):
      """
      Certifier for enum values.
  
      :param value:
          The value to be certified.
      :param kind:
          The enum type that value should be an instance of.
      :param bool required:
          Whether the value can be `None`. Defaults to True.
      :raises CertifierValueError:
          The type is invalid
      """
      if certify_required(
          value=value,
          required=required,
      ):
          return
  
      try:
          kind(value)
      except:  # noqa
          raise CertifierValueError(
              message="value {value!r} is not a valid member of {enum!r}".format(
                  value=value, enum=kind.__name__),
              value=value,
              required=required,
          )