psqlextra/manager/manager.py
def _is_magical_field(self, model_instance, field, is_insert: bool):
        """Verifies whether this field is gonna modify something
        on its own.

        "Magical" means that a field modifies the field value
        during the pre_save.

        Arguments:
            model_instance:
                The model instance the field is defined on.

            field:
                The field to get of whether the field is
                magical.

            is_insert:
                Pretend whether this is an insert?

        Returns:
            True when this field modifies something.
        """

        # does this field modify someting upon insert?
        old_value = getattr(model_instance, field.name, None)
        field.pre_save(model_instance, is_insert)
        new_value = getattr(model_instance, field.name, None)

        return old_value != new_value
def _is_magical_field(self, model_instance, field, is_insert: bool):
        """Verifies whether this field is gonna modify something
        on its own.

        "Magical" means that a field modifies the field value
        during the pre_save.

        Arguments:
            model_instance:
                The model instance the field is defined on.

            field:
                The field to get of whether the field is
                magical.

            is_insert:
                Pretend whether this is an insert?

        Returns:
            True when this field modifies something.
        """

        # does this field modify someting upon insert?
        old_value = getattr(model_instance, field.name, None)
        field.pre_save(model_instance, is_insert)
        new_value = getattr(model_instance, field.name, None)

        return old_value != new_value
Verifies whether this field is gonna modify something
        on its own.

        "Magical" means that a field modifies the field value
        during the pre_save.

        Arguments:
            model_instance:
                The model instance the field is defined on.

            field:
                The field to get of whether the field is
                magical.

            is_insert:
                Pretend whether this is an insert?

        Returns:
            True when this field modifies something.