code: def set_index(self, indexes=None, append=False, inplace=None,
                    **indexes_kwargs):
          
          inplace = _check_inplace(inplace)
          indexes = either_dict_or_kwargs(indexes, indexes_kwargs, 'set_index')
          coords, _ = merge_indexes(indexes, self._coords, set(), append=append)
          if inplace:
              self._coords = coords
          else:
              return self._replace(coords=coords)
docs: Set DataArray (multi-)indexes using one or more existing
          coordinates.
  
          Parameters
          ----------
          indexes : {dim: index, ...}
              Mapping from names matching dimensions and values given
              by (lists of) the names of existing coordinates or variables to set
              as new (multi-)index.
          append : bool, optional
              If True, append the supplied index(es) to the existing index(es).
              Otherwise replace the existing index(es) (default).
          inplace : bool, optional
              If True, set new index(es) in-place. Otherwise, return a new
              DataArray object.
          **indexes_kwargs: optional
              The keyword arguments form of ``indexes``.
              One of indexes or indexes_kwargs must be provided.
  
          Returns
          -------
          obj : DataArray
              Another dataarray, with this data but replaced coordinates.
  
          See Also
          --------
          DataArray.reset_index