def error(self, value):
        """Helper method that can be called when ``value`` is deemed invalid.
        Can be overriden to provide customized :py:exc:`ValidationError` subclasses.
        """
        raise ValidationError("must be %s" % self.humanized_name, value)
dataset/ETHPy150Open sdispater/cleo/cleo/validators/__init__.py/Validator.error/original