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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 parametrize(self):
 r""" Reads all data and discretizes it into discrete trajectories. """

        for element in self._chain:
            if not element.is_reader and not element._estimated:
                element.estimate(element.data_producer, stride=self.param_stride, chunksize=self.chunksize)

        self._estimated = True