1. For python system library's common path, please use as below.
2. Change the permission for your .py script, to allow executable.
Shell> chmod a+x scriptname.py
For example : chmod a+x index.py
3. Please make sure the owner of the script is your hosting account username. If not, change the owner with below command.
Shell> chown username.username scriptname.py
For example : chown exabytes.exabytes index.py