I guess that you dont have any names in your guest_names.txt file (eventually you start with no file). You are going through names in your names list and for each name you compare it with username and if they are different, you append username to a file. What will happen if there is no name in your list to start with? And what will happen if there is multiple names in your file?
Perhaps you should change your for loop so its used only to check if username is taken or no.
Creating empty file so you can read empty list from it seems little odd. Isnt easier to just put
Perhaps you should change your for loop so its used only to check if username is taken or no.
Creating empty file so you can read empty list from it seems little odd. Isnt easier to just put
names = [] if there is no file? (you dont need existing file to append to it).