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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 pretty_print(self):
 """Use `PrettyTable` to perform formatted outprint."""

        pt = PrettyTable()
        if len(self) == 0:
            pt._set_field_names(['Sorry,'])
            pt.add_row([TRAIN_NOT_FOUND])
        else:
            pt._set_field_names(self.headers)
            for train in self.trains:
                pt.add_row(train)
        print(pt)