code: def _load(self, config):
          
          if isinstance(config, six.string_types):
              try:
                  config = json.loads(config)
              except ValueError:
                  pass
          if not isinstance(config, dict):
              raise TypeError('config block must be an istance '
                              'of dict or a valid NetJSON string')
          return config
docs: Loads config from string or dict