使用python将字符附加到txt文件中的每一行(Appending characters to each line in a txt file with python)

 我写了下面的python代码片段，在txt文件的每一行附加一个较低的p字符： 
 
f = open('helloworld.txt','r')
for line in f:
    line+='p'
print(f.read())
f.close()
 
 但是，当我执行这个python程序时，它只返回一个空的空白： 
 
zhiwei@zhiwei-Lenovo-Rescuer-15ISK:~/Documents/1001/ass5$ python3 helloworld.py
 
 谁能告诉我我的代码有什么问题？ 

I wrote the following python code snippet to append a lower p character to each line of a txt file:
 
f = open('helloworld.txt','r')
for line in f:
    line+='p'
print(f.read())
f.close()
 
However, when I execute this python program, it returns nothing but an empty blank:
 
zhiwei@zhiwei-Lenovo-Rescuer-15ISK:~/Documents/1001/ass5$ python3 helloworld.py
 
Can anyone tell me what's wrong with my codes?

原文：https://stackoverflow.com/questions/47276506