[MM3-users] Cloned mailman3 from the gitlab site, having issues locating the mailman3 file to start it

The path to the mailman3.py file is: /home/mailman3/mailman/src/mailman/bin/mailman.py I created a mailman3 user, then, set the ownership on all directories and files in /home/mailman3 and below to mailman3:mailman3.

When trying to run the "mailman info" command to verify that that mailman3 can start, I get this error:

File "/home/mailman3/mailman/src/mailman/bin/mailman.py", line 22 in <module> from mailman.command.cli_help import help as help command

Not sure what is going on here, help greatly appreciated.