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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 productinfo(self):
 """Return the productversion and channel of this MAR if present."""

        if not self.mardata.additional:
            return None

        for s in self.mardata.additional.sections:
            if s.id == 1:
                return str(s.productversion), str(s.channel)

        return None