rename.py

def _columns_in_table(table: Set[Record]) -> set:
    return set.union(*[set(record.keys()) for record in table])

def rename(table: Set[Record], columns: dict) -> Set[Record]:
    table_columns = _columns_in_table(table)
    table_out = {
        Record({columns.get(old_name, old_name): record[old_name] for old_name in table_columns})
        for record in table
    }
    return table_out