def invoke(self, context):
        try:
            method = getattr(self.controller,
                             ec2utils.camelcase_to_underscore(self.action))
        except __HOLE__:
            LOG.exception(_('Unsupported API request: action = %(action)s'),
                          {'action': self.action})
            raise exception.InvalidRequest()

        args = ec2utils.dict_from_dotted_str(self.args.items())

        def convert_dicts_to_lists(args):
            if not isinstance(args, dict):
                return args
            for key in args.keys():
                # NOTE(vish): Turn numeric dict keys into lists
                # NOTE(Alex): Turn "value"-only dict keys into values
                if isinstance(args[key], dict):
                    if args[key] == {}:
                        continue
                    first_subkey = next(six.iterkeys(args[key]))
                    if first_subkey.isdigit():
                        s = args[key]
                        args[key] = [convert_dicts_to_lists(s[k])
                                     for k in sorted(s)]
                    elif (first_subkey == 'value' and
                            len(args[key]) == 1):
                        args[key] = args[key]['value']
            return args

        args = convert_dicts_to_lists(args)
        result = method(context, **args)
        return self._render_response(result, context.request_id)
dataset/ETHPy150Open openstack/ec2-api/ec2api/api/apirequest.py/APIRequest.invoke