Recipe for interactive python command line application (REPL).

interactive.py

import sys
from optparse import OptionParser
 
def command(options, args):
  function, parameters = args[0], args[1:]
 
  print "You typed: {0}({1})".format(function, parameters)
 
def interactive(options, args):
  print "Python interactive window.  Type $help for a list of commands."
  
  while True:
    sys.stdout.write(">>> ")
 
    line = sys.stdin.readline().strip()
 
    if line.lower() in ["quit", "q", "exit"]:
      break
 
    columns = line.split(" ")
    command(options, columns)
 
def main():
  parser = OptionParser(usage='usage: %prog [options]', version="%prog {0}".format(__version__))
  (options, args) = parser.parse_args()
 
  interactive(options, args)
 
if __name__ == '__main__':
  main()