You can change default PHP version in SSH terminal:
$ cp -f /usr/local/lsws/lsphp80/bin/php /usr/bin/
The default php.ini locations
/usr/local/lsws/lsphp80/etc/php.ini
/usr/local/lsws/lsphp74/etc/php.ini
/usr/local/lsws/lsphp73/etc/php.ini
/usr/local/lsws/lsphp72/etc/php.ini
/usr/local/lsws/lsphp71/etc/php.ini
/usr/local/lsws/lsphp70/etc/php.ini
/usr/local/lsws/lsphp56/etc/php.ini
/usr/local/lsws/lsphp55/etc/php.ini
/usr/local/lsws/lsphp54/etc/php.ini
/usr/local/lsws/lsphp53/etc/php.ini
You can run the script e.g.
$ /usr/local/lsws/lsphp80/bin/php shell_exec ("/my/script.py");
If its a permission issue follow this Shell_exec returns permissions error - #5 by chillyplate and see if it works for you
You can add a sink for the command e.g.
$ /usr/local/lsws/lsphp80/bin/php shell_exec("/home/mydomain.com/my_script.py 2>&1 | tee -a /home/mydomain.com/errorlog 2>/dev/null >/dev/null &");
OR better yet write a full script to run it e.g. php script would look like
<?php
$command = "run sth here";
shell_exec($command);
?>
place this somewhere in documentroot to run it