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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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]))