code: def set_geom_opt_coords_type(self, coords_type="internal_switch"):
          
          coords_map = {"cartesian": 0, "internal": 1, "internal-switch": -1,
                        "z-matrix": 2, "z-matrix-switch": -2}
          if coords_type.lower() not in set(coords_map.keys()):
              raise ValueError("Coodinate system " + coords_type + " is not "
                               "supported yet")
          else:
              self.params["rem"]["geom_opt_coords"] = \
                  coords_map[coords_type.lower()]
docs: Set the coordinates system used in geometry optimization.
          "cartesian"       --- always cartesian coordinates.
          "internal"        --- always internal coordinates.
          "internal-switch" --- try internal coordinates first, if fails, switch
          to cartesian coordinates.
          "z-matrix"        --- always z-matrix coordinates.
          "z-matrix-switch" --- try z-matrix first, if fails, switch to
          cartesian coordinates.
  
          Args:
              coords_type: The type of the coordinates. (str)