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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 make_patch(self):
        '''Currently only works if all the pieces are Arcgons.
           In this case returns a multiple-piece path. Otherwise throws an exception.'''
        paths = [p.make_patch().get_path() for p in self.pieces]
        vertices = np.concatenate([p.vertices for p in paths])
        codes = np.concatenate([p.codes for p in paths])
        return PathPatch(Path(vertices, codes))