commands
import commands
commands.getstatusoutput(cmd)         返回(status, output)
commands.getoutput(cmd)                   只返回输出结果
os
import os 
os.system("echo \"Hello World\"")
or
print os.popen('ls -lt').read()
传shell的参数
import os
var=123或var='123'
os.environ['var']=str(var) #environ的键值必须是字符串
os.system('echo $var')
import os
var='123'
os.popen('wc -c', 'w').write(var)