Santosh,
Yes. Hooks on UNIX/Linux environments run in bash and hooks on Windows environment run in powershell.
Either way, you can start a python script as you would normally in either of those shells (i.e. "python script-name.py", etc).
The trick is likely exiting from shell with the exit status from the script, so follow the call to the python script with "exit $?" in bash and perhaps "exit $LastExitCode" or "exit $?" in powershell.
Hope this helps?
-Tim