How to pass variable from php to python in cyberpanel

<?php $my_username = "094009"; $command = escapeshellcmd("python /home/ $my_username"); $output = exec($command); echo $output; ?>

that is the php code that runs the python, but the $my_username variable doesn’t pass to the python code, any suggestion?
i use the lates cyberpanel version, an i use php 7.3

you can pass some script for python like shell_exec() and in it you can pass variable