为了提升自已零基础编程能力，采取多种方式学习Python，其中包括跟随《笨办法》步步学习，现将其中练习17的代码分享给大家，对于曾经遇到同样疑难的同志给予帮助。代码如下：

# python ex17.py 将一个文件中的内容拷贝到另外一个文件中。

from sys import argv

from os.path import exists

script, from_file, to_file = argv

print ("Copying from %s to %s " % (from_file, to_file))

# We could do these two on one line too, how?

in_put = open(from_file)    # 此处有些资料可能会显示为“input = ”

indata = in_put.read()

print ("The input file is %d byes long " % len(indata))

print ("Does the output file exist? %r " % exists(to_file))

print ("Ready, hit RETURN to continue, CTRL-C to abort.")

input ()

output = open(to_file, 'w')

output.write(indata)

print ("Alright, all done.")

output.close()

in_put.close()  # 关闭已打开的 in_put文件，注意：是in_put，不是input