code: def get_axis_num(self, dim: Union[Hashable, Iterable[Hashable]]
                       ) -> Union[int, Tuple[int, ...]]:
          
          if isinstance(dim, Iterable) and not isinstance(dim, str):
              return tuple(self._get_axis_num(d) for d in dim)
          else:
              return self._get_axis_num(dim)
docs: Return axis number(s) corresponding to dimension(s) in this array.
  
          Parameters
          ----------
          dim : str or iterable of str
              Dimension name(s) for which to lookup axes.
  
          Returns
          -------
          int or tuple of int
              Axis number or numbers corresponding to the given dimensions.