docs: def load_yaml(data=None, path=None, name='NT'):
      """ Map namedtuples with yaml data. """
      if data and not path:
          return mapper(yaml.load(data), _nt_name=name)
      if path and not data:
          with open(path, 'r') as f:
              data = yaml.load(f)
          return mapper(data, _nt_name=name)
      if data and path:
          raise ValueError('expected one source and received two')