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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 tt_avg(self, print_output=True, output_file="tt.csv"):
 """ Compute average term-topic matrix, and print to file if print_output=True. """


        avg = self.tt.mean(axis=2)
        if print_output:
            np.savetxt(output_file, avg, delimiter=",")
        return avg