def _CheckRequiredLoadOptions(self):
    for option in ['filename']:
      if getattr(self.options, option) is None:
        self.parser.error('Option \'%s\' is required.' % option)
    if not self.options.url:
      self.parser.error('You must have google.appengine.ext.remote_api.handler '
                        'assigned to an endpoint in app.yaml, or provide '
                        'the url of the handler via the \'url\' option.')
Serialize to JSON dict
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/tools/appcfg.py/AppCfgApp._CheckRequiredLoadOptions--crossover with--dataset/ETHPy150Open ucb-sts/sts/sts/entities/hosts.py/HostInterfaceAbstractClass.to_json