def clean(self, value):
        """
        Validates that the input is a list or tuple.
        """
        if self.required and not value:
            raise ValidationError(self.error_messages['required'])
        elif not self.required and not value:
            return []
        if not isinstance(value, (list, tuple)):
            raise ValidationError(self.error_messages['invalid_list'])
        new_value = [smart_unicode(val) for val in value]
        # Validate that each value in the value list is in self.choices.
        for val in new_value:
            if not self.valid_value(val):
                raise ValidationError({'value': val} % self.error_messages['invalid_choice'])
        return new_value
dataset/ETHPy150Open CollabQ/CollabQ/vendor/django/forms/fields.py/MultipleChoiceField.clean/swapped operands of `%`