#!/usr/bin/env python

codestring = 'foo = "new"'

open ("execfile", "w").write (codestring)

if 1:
   foo = 'old'
   exec codestring
   print "global:     exec: foo = " + foo

   foo = 'old'
   execfile ("execfile")
   print "global: execfile: foo = " + foo


def main ():
   foo = 'old'
   exec codestring
   print "func:       exec: foo = " + foo

   foo = 'old'
   execfile ("execfile")
   print "func:   execfile: foo = " + foo


main ()