There is likely a way to do this by embedding the admin's username and sudo password into the script. (Which is the way I originally had it set up.) Of course this comprimises security, so I wouldn't recommend it if you are worried about your normal users finding the script. Something like this may work:
Originally Posted by robbuntista
retcode = subprocess.call("sudo /etc/init.d/umountnfs.sh", shell=True)
Replace admin's_sudo_password and admin's_username with your sudo password and username.
retcode = subprocess.call("echo admin's_sudo_password | sudo -u admin's_username -S /etc/init.d/umountnfs.sh", shell=True)