當我們在生成數據的時候，常用到%d方式進行格式化生成數據。
比如要生成11位的手機號，可以這樣：
def test_create_data(): data = ['138%08d' %x for x in range(20)] print(data)
當填充內容不足8位的時候，用0進行填充輸出內容：
['13800000000', '13800000001', '13800000002', '13800000003', '13800000004', '13800000005', '13800000006', '13800000007', '13800000008', '13800000009', '13800000010', '13800000011', '13800000012', '13800000013', '13800000014', '13800000015', '13800000016', '13800000017', '13800000018', '13800000019']
詳細用法參考博客：https://blog.csdn.net/lijing742180/article/details/80788422