membership test should be 'not in'

generic_parser/dict_parser.py

@@ -160,7 +160,7 @@ def _parse_arguments(self, arg_dict, param_dict):
  checked_dict[key] = DictParser._check_value(key, arg_dict, param_dict)
  elif isinstance(param_dict[key], dict):
  try:
- if not arg_dict or not (key in arg_dict):
+ if not arg_dict or key not in arg_dict:
  checked_dict[key] = self._parse_arguments({}, param_dict[key])[0]
  else:
  checked_dict[key] = self._parse_arguments(arg_dict[key], param_dict[key])[0]