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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 expect(self, use_proportions=True):
 """ The Expectation step of the CEM algorithm """

        changed = self.get_changed(self.partition, self.prev_partition)
        lk_table = self.generate_lktable(self.partition, changed, use_proportions)
        self.table = self.likelihood_table_to_probs(lk_table)