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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 unregisterContextEngineId(self, contextEngineId, pduTypes):
 """Unregister application with dispatcher"""


        # 4.3.4
        if contextEngineId is None:
            # Default to local snmpEngineId
            contextEngineId, = self.mibInstrumController.mibBuilder.importSymbols(
                '__SNMP-FRAMEWORK-MIB', 'snmpEngineID')

        for pduType in pduTypes:
            k = contextEngineId, pduType
            if k in self._appsRegistration:
                del self._appsRegistration[k]

        debug.logger & debug.FLAG_DSP and debug.logger(
            'unregisterContextEngineId: contextEngineId %r pduTypes '
            '%s' % (contextEngineId, pduTypes))