


We are going to create a virtual environment using virtualenv. But before we install them, let's create a virtual environment and activate it. While you're coding this project, you'll come across various modules and external libraries. But hey, your favorite programming language Python can help you with that. Oops, did you forget he is no more? It's sad that he can no longer save us. Have you ever wondered whether you could create your own personal assistant? Yes? Tony Stark can help us with that! (Note this command also removes the diff formatting after it gets the right lines.Do you remember J.A.R.V.I.S., Tony Stark's virtual personal assistant? If you've seen any of the Ironman or Avengers movies, I'm sure you do. You could do this by creating a diff file with the context value at 100% of the lines in the file, then parsing it for just the lines that would be removed if converting file A to file B.

The solution to that is to use a real comparison tool such as diff. The downside of this solution is that it doesn't take line order into account and if your input has duplicate lines in different places you might not get what you expect. Therefore you are printing out the lines in fileA that don't contain the same data as any line in fileB. You force the match to happen on the whole line ( -x) and print out only the lines that don't match ( -v). This works by using each line in fileB as a pattern ( -f fileB) and treating it as a plain string to match (not a regular regex) ( -F). The standard grep tool for searching files for text strings can be used to subtract all the lines in one file from another.
