def fields_referencing(self, tbl, column=None):
        if self.tables not in tbl:
            raise StopIteration()
        for c in self.tables[tbl].columns:
            for r in c.referenced_by:
                if column is None or column == r.referenced_column.name:
                    yield ForeignKey(r.table.name, (r.name,), tbl, (c.name,))
dataset/ETHPy150Open jaysw/ipydb/ipydb/metadata/model.py/Database.fields_referencing/swapped operands of `not in`