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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 perplexity(self):
 """ Compute perplexity for each sample. """


        return samplers_lda.perplexity_comp(self.docid, self.tokens,
                                            self.tt, self.dt, self.N,
                                            self.K, self.samples)