基本常识

1. python中的左位移和右位移
2. 利用Python在一个文件的头部插入数据

            
              with open(path, "r+") as f:
     old = f.read()
     f.seek(0)
     f.write(data)
     f.write(old)

            
          

Debug

1. xpath中遇到[ ]
2. AttributeError: ‘dict’ object has no attribute ‘iteritems’

Python3.5中：iteritems变为items

3. 【Python】ufunc ‘subtract’ did not contain a loop with signature matching types dtype
4. Pycharm 下Non-ASCII character ‘\xe5’ in file… 解决办法

            
              # -*- coding: utf-8 -*-：

            
          

5. Python mysqldb执行execute时出现InterfaceError: (0, ‘’)

P.K.

1. Python中下划线的5种含义
2. python 单下划线及双下划线使用总结
3. python中open()函数中可选参数w，w+和a，a+的区别

实战演练

Python mysql表数据和json格式的相互转换