def _Nag(self, msg, latest, version, force=False):
    nag = self._ParseNagFile()
    if nag and not force:
      last_nag = datetime.datetime.fromtimestamp(nag.timestamp)
      if datetime.datetime.now() - last_nag < datetime.timedelta(weeks=1):
        logging.debug('Skipping nag message')
        return

    if nag is None:
      nag = NagFile()
    nag.timestamp = time.time()
    self._WriteNagFile(nag)

    print '****************************************************************'
    print msg
    print '-----------'
    print 'Latest SDK:'
    print yaml.dump(latest)
    print '-----------'
    print 'Your SDK:'
    print yaml.dump(version)
    print '-----------'
    print 'Please visit http://code.google.com/appengine for the latest SDK'
    print '****************************************************************'
Prints a nag message and updates the nag file's timestamp.
dataset/ETHPy150Open CollabQ/CollabQ/.google_appengine/google/appengine/tools/appcfg.py/UpdateCheck._Nag