replace lines 8 to 11 with
users.extend(g[3].split(','))as a side note - using one-letter names is bad, use descriptive names
If you can't explain it to a six year old, you don't understand it yourself, Albert Einstein
How to Ask Questions The Smart Way: link and another link
Create MCV example
Debug small programs
How to Ask Questions The Smart Way: link and another link
Create MCV example
Debug small programs