8.6 Project: multiple Clipboard-when there is no instance operation verification, it is really annoying

The real pleasure of getting done with this project lies in the hint in the article, "recall the password safe deposit box program created in Chapter 6."

The key and difficult point of this chapter should be to understand that the shelve module is a temporary database that can constantly assign strings on the clipboard to specified keywords and store them in three temporary files with mcb switches in the form of dictionaries (I wonder if it will disappear after restarting the computer). Another important and difficult point is to deepen the understanding of the role of the sys.argv function, which can include N parameters, but the first parameter is always the python file itself, and the other parameters must be written in the form of% * at the end of the bat script to correspond to more than the second parameter.

The specific verification steps are shown below:

The purpose of these three files at the beginning of mcb is that the shelve module is used to store some keywords as keys similar to dictionaries to save the strings on the clipboard as dictionary values.