写python经常忘记方法名，在用linux的时候都习惯用tab补全命令，所以创建tab.py

#!/usr/bin/env python 
# python startup file 
import sys
import readline
import rlcompleter
import atexit
import os
# tab completion 
readline.parse_and_bind('tab: complete')
# history file 
histfile = os.path.join(os.environ['HOME'], '.pythonhistory')
try:
    readline.read_history_file(histfile)
except IOError:
    pass
atexit.register(readline.write_history_file, histfile)
del os, histfile, readline, rlcompleter

将脚本放在指定位置，可以用sys.path查看路径

>>import sys
>>sys.path

一般我们会将这一类代码放在/usr/local/lib/python2.7/dist-packages目录下

mv tab.py /usr/local/lib/python2.7/dist-packages