程序代码：

from sys import argv

script, filename = argv

txt = open(filename)

print(f"Here's your file {filename}:")
print(txt.read())

print("Type the filename again:")
file_again = input("> ")

txt_again = open(file_again)

print(txt_again.read())

输出结果：

PS D:\lpthw> python ex15.py ex15_sample.txt
Here's your file ex15_sample.txt:
This is stuff I typed into a file.
It is really cool stuff.
Lots and lots of fun to have in here.
Type the filename again:
> ex15_sample.txt
This is stuff I typed into a file.
It is really cool stuff.
Lots and lots of fun to have in here.