Python内置读写文件的基本操作函数，并且支持with语句，可以更加方便的管理相关的资源。

示例代码如下：

with open('d:/test.txt','rt') as rf:
    data=rf.read()
    print(data)
    
with open('d:/test.txt',"at") as wf:
    wf.write("Hello Python!\n")
    wf.write("Hello PyDev!\n")
    print("Hello World!",file=wf)
    
with open('d:/test.txt') as rf:
    for line in rf:
        print(line,end='')

参考资料：

http://docs.python.org/3/library/functions.html#open

http://docs.python.org/3/reference/compound_stmts.html#with