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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 append_segment(self, apdu):
 """This function appends the apdu content to the end of the current APDU being built. The segmentAPDU is the context."""

        if _debug: SSM._debug("append_segment %r", apdu)

        # check for no context
        if not self.segmentAPDU:
            raise RuntimeError("no segmentation context established")

        # append the data
        self.segmentAPDU.put_data(apdu.pduData)