python curses

#!/usr/bin/env pythonfrom os import systemimport cursesdef get_param(PRompt_string):     screen.clear()     screen.border(0)     screen.addstr(2, 2, prompt_string)     screen.refresh()     input = screen.getstr(10, 10, 60)     return inputdef execute_cmd(cmd_string):     system("clear")     a = system(cmd_string)     print ""     if a == 0:          print "Command executed correctly"     else:          print "Command terminated with error"     raw_input("Press enter")     print "" x = 0 
while x != ord('4'):
     screen = curses.initscr()      screen.clear()     screen.border(0)     screen.addstr(2, 2, "Please enter a number...")     screen.addstr(4, 4, "1 - Add a user")     screen.addstr(5, 4, "2 - Restart Apache")     screen.addstr(6, 4, "3 - Show disk space")     screen.addstr(7, 4, "4 - Exit")     screen.refresh()     x = screen.getch()     if x == ord('1'):          username = get_param("Enter the username")          homedir = get_param("Enter the home directory, eg /home/nate")          groups = get_param("Enter comma-separated groups, eg adm,dialout,cdrom")          shell = get_param("Enter the shell, eg /bin/bash:")          curses.endwin()          execute_cmd("useradd -d " + homedir + " -g 1000 -G " + groups + " -m -s " + shell + " " + username)     if x == ord('2'):          curses.endwin()          execute_cmd("apachectl restart")     if x == ord('3'):          curses.endwin()          execute_cmd("df -h")curses.endwin()