Override-ing ValidationError throws => ValueError: too many values to unpack (expected 2)

[Kevi14]

Was trying to create a custom ValueError for my application with the below code.

class CValidationError(serializers.ValidationError):
    pass


class CustomErrorMessagesModelSerializer(ModelSerializer):

    def __init__(self, *args, **kwargs):
        super(CustomErrorMessagesModelSerializer,
              self).__init__(*args, **kwargs)

    def to_internal_value(self, data):
        """
        Dict of native values <- Dict of primitive datatypes.
        """
        if not isinstance(data, Mapping):
            message = self.error_messages['invalid'].format(
                datatype=type(data).__name__
            )
            raise ValidationError({
                api_settings.NON_FIELD_ERRORS_KEY: [message]
            }, code='invalid')

        ret = OrderedDict()
        errors = OrderedDict()
        fields = self._writable_fields

        for field in fields:

            validate_method = getattr(
                self, 'validate_' + field.field_name, None)
            primitive_value = field.get_value(data)
            try:
                validated_value = field.run_validation(primitive_value)
                if validate_method is not None:
                    validated_value = validate_method(validated_value)
            except CValidationError as exc:
                errors[field.field_name] = exc.detail
                print(exc.detail)
            # except DjangoValidationError as exc:
            #     errors[field.field_name] = get_error_detail(exc)
            except SkipField:
                pass
            else:
                set_value(ret, field.source_attrs, validated_value)

        if errors:
            raise CValidationError(errors)

        return ret

However it throws this error.

`back_1   | Traceback (most recent call last):
back_1   |   File "/usr/local/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
back_1   |     response = get_response(request)
back_1   |   File "/usr/local/lib/python3.8/site-packages/django/core/handlers/base.py", line 181, in _get_response
back_1   |     response = wrapped_callback(request, *callback_args, **callback_kwargs)
back_1   |   File "/usr/local/lib/python3.8/site-packages/django/views/decorators/csrf.py", line 54, in wrapped_view
back_1   |     return view_func(*args, **kwargs)
back_1   |   File "/usr/local/lib/python3.8/site-packages/rest_framework/viewsets.py", line 125, in view
back_1   |     return self.dispatch(request, *args, **kwargs)
back_1   |   File "/usr/local/lib/python3.8/site-packages/rest_framework/views.py", line 509, in dispatch
back_1   |     response = self.handle_exception(exc)
back_1   |   File "/usr/local/lib/python3.8/site-packages/rest_framework/views.py", line 469, in handle_exception
back_1   |     self.raise_uncaught_exception(exc)
back_1   |   File "/usr/local/lib/python3.8/site-packages/rest_framework/views.py", line 480, in raise_uncaught_exception
back_1   |     raise exc
back_1   |   File "/usr/local/lib/python3.8/site-packages/rest_framework/views.py", line 506, in dispatch
back_1   |     response = handler(request, *args, **kwargs)
back_1   |   File "/usr/local/lib/python3.8/site-packages/rest_framework/mixins.py", line 18, in create
back_1   |     serializer.is_valid(raise_exception=True)
back_1   |   File "/usr/local/lib/python3.8/site-packages/rest_framework/serializers.py", line 228, in is_valid
back_1   |     raise ValidationError(self.errors)
back_1   |   File "/usr/local/lib/python3.8/site-packages/rest_framework/serializers.py", line 559, in errors
back_1   |     return ReturnDict(ret, serializer=self)
back_1   |   File "/usr/local/lib/python3.8/site-packages/rest_framework/utils/serializer_helpers.py", line 18, in __init__
back_1   |     super().__init__(*args, **kwargs)
back_1   | ValueError: too many values to unpack (expected 2)

Is this an internal bug ?