docs: def query(self, coords):
          """
          Args:
              coords (`astropy.coordinates.SkyCoord`): The coordinates to query.
  
          Returns:
              A float array of the value of the map at the given coordinates. The
              shape of the output is the same as the shape of the coordinates
              stored by `coords`.
          """
          pix_idx = coord2healpix(coords, self._frame,
                                  self._nside, nest=self._nest)
          return self._pix_val[pix_idx]