def get_related_field_alias(self) -> str:
        """
        Extract names of the related database columns or that are connected
        with given relation based to use as a target in filter clause.

        :return: name or names of the related columns/ fields
        :rtype: Union[str, Dict[str, str]]
        """
        if self.self_reference and self.self_reference_primary == self.name:
            field_name = self.default_target_field_name()
        else:
            field_name = self.default_source_field_name()
        sub_field = self.through.ormar_config.model_fields[field_name]
        return sub_field.get_alias()

        Extract names of the related database columns or that are connected
        with given relation based to use as a target in filter clause.

        :return: name or names of the related columns/ fields
        :rtype: Union[str, Dict[str, str]]
        
ormar/fields/many_to_many.py