Returns the different inherited schemas for this instance.

        :return     [<TableSchema>, ..]

def ancestry(self):
        """
        Returns the different inherited schemas for this instance.

        :return     [<TableSchema>, ..]
        """
        if not self.inherits():
            return []

        schema = orb.system.schema(self.inherits())
        if not schema:
            return []

        return schema.ancestry() + [schema]