docs: def get_nodes(self, coord, coords):
          """Get the variables containing the definition of the nodes
  
          Parameters
          ----------
          coord: xarray.Coordinate
              The mesh variable
          coords: dict
              The coordinates to use to get node coordinates"""
          def get_coord(coord):
              return coords.get(coord, self.ds.coords.get(coord))
          return list(map(get_coord,
                          coord.attrs.get('node_coordinates', '').split()[:2]))