code: def do_py(self, arg):
          
          self.pystate['self'] = self
          arg = arg.strip()
          localvars = (self.locals_in_py and self.pystate) or {}
          interp = InteractiveConsole(locals=localvars)
          interp.runcode('import sys, os;sys.path.insert(0, os.getcwd())')
          if arg:
              interp.runcode(arg)
          else:
              def quit():
                  raise EmbeddedConsoleExit
  
              def onecmd(arg):
                  return self.onecmd(arg + '\n')
  
              def run(arg):
                  try:
                      f = open(arg)
                      interp.runcode(f.read())
                      f.close()
                  except IOError, e:
                      self.perror(e)
              self.pystate['quit'] = quit
              self.pystate['exit'] = quit
              self.pystate['cmd'] = onecmd
              self.pystate['run'] = run
              try:
                  cprt = 'Type "help", "copyright", "credits" or "license" for more information.'
                  keepstate = Statekeeper(sys, ('stdin', 'stdout'))
                  sys.stdout = self.stdout
                  sys.stdin = self.stdin
                  interp.interact(banner="Python %s on %s\n%s\n(%s)\n%s" %
                                  (sys.version, sys.platform, cprt, self.__class__.__name__, self.do_py.__doc__))
              except EmbeddedConsoleExit:
                  pass
              keepstate.restore()
docs: ::
  
              Usage:
                  py
                  py COMMAND
  
              Arguments:
                  COMMAND   the command to be executed
  
              Description:
  
                  The command without a parameter will be executed and the
                  interactive python mode is entered. The python mode can be
                  ended with ``Ctrl-D`` (Unix) / ``Ctrl-Z`` (Windows),
                  ``quit()``,'`exit()``. Non-python commands can be issued with
                  ``cmd("your command")``.  If the python code is located in an
                  external file it can be run with ``run("filename.py")``.
  
                  In case a COMMAND is provided it will be executed and the
                  python interpreter will return to the command shell.
  
                  This code is copied from Cmd2.