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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 abort(self, reason):
 """This function is called when the application would like to abort the transaction. There is no notification back to the application."""

        if _debug: ServerSSM._debug("abort %r", reason)

        # change the state to aborted
        self.set_state(ABORTED)

        # return an abort APDU
        return AbortPDU(True, self.invokeID, reason)