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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 confirmation(self, pdu):
 """Decode upstream PDUs and pass them up to the service access point."""

        if _debug: NetworkAdapter._debug("confirmation %r (net=%r)", pdu, self.adapterNet)

        npdu = NPDU(user_data=pdu.pduUserData)
        npdu.decode(pdu)
        self.adapterSAP.process_npdu(self, npdu)