>>> f=open ('py3test.txt','wt',encoding='utf8')
>>> f.write('你好,我爱编程')
7
>>> f.close()
>>> f=open ('py3test.txt','rt',encoding='utf8')
>>> s=f.read()
>>> print(s)
你好,我爱编程
>>>
>>> f=open ('py3test.txt','wt',encoding='utf8')
>>> f.write('你好,我爱编程')
7
>>> f.close()
>>> f=open ('py3test.txt','rt',encoding='utf8')
>>> s=f.read()
>>> print(s)
你好,我爱编程
>>>