def add_expression_column(table, new_cols, formulas, expr_type='sqlite'):
    _table = table.copy()
    print(locals())
    for (nc, f) in zip(new_cols, formulas):
        if (expr_type == 'sqlite'):
            _table[nc] = sqldf('select {f} as new_val from _table'.format(f=f))
        else:
            _table[nc] = _table.eval(f, engine=expr_type)
    return {'out_table': _table}
def add_expression_column(table, new_cols, formulas, expr_type='sqlite'):
    _table = table.copy()
    print(locals())
    for (nc, f) in zip(new_cols, formulas):
        if (expr_type == 'sqlite'):
            _table[nc] = sqldf('select {f} as new_val from _table'.format(f=f))
        else:
            _table[nc] = _table.eval(f, engine=expr_type)
    return {'out_table': _table}