This is the python linter disagreeing with your code style.
For example, it likes "nb_produits * int(input())" not "nb_produits*int(input())".
Each thing it doesn't like, it will tell you in the message bar at the bottom.
If you don't like the linting, go to a file named "Anaconda.sublime-settings" and look for the option "anaconda_linting": true. (Set to false.)
- keep the linting for now, to get used to it at least before you decide to turn it off
- change "anaconda_linting_behavior" to "save-only" in the same file, or the linting will drive you nuts!
(If you can't find the file I just mentioned, install something called PackageResourceViewer, and use this to extract the anaconda package. Then you will find the Anaconda.sublime-settings file in that directory.)