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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 set_pointlist(self, pointlist):
 """Overwrite pointlist. Parameters pointlist : a list of strokes; each stroke is a list of points The inner lists represent strokes. Every stroke consists of points. Every point is a dictinary with 'x', 'y', 'time'. """

        assert type(pointlist) is list, \
            "pointlist is not of type list, but %r" % type(pointlist)
        assert len(pointlist) >= 1, \
            "The pointlist of formula_id %i is %s" % (self.formula_id,
                                                      self.get_pointlist())
        self.raw_data_json = json.dumps(pointlist)