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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 addVarBinds(self, *varBinds):
 """Appends variable-binding to notification. Parameters *varBinds : :py:class:`~pysnmp.smi.rfc1902.ObjectType` One or more :py:class:`~pysnmp.smi.rfc1902.ObjectType` class instances. Returns ------- : :py:class:`~pysnmp.smi.rfc1902.NotificationType` reference to itself Notes ----- This method can be used to add custom variable-bindings to notification message in addition to MIB variables specified in NOTIFICATION-TYPE->OBJECTS clause. Examples -------- NotificationType(ObjectIdentity('IP-MIB', 'linkDown'), (), {}) """

        debug.logger & debug.FLAG_MIB and debug.logger(
            'additional var-binds: %r' % (varBinds,))

        if self._state & self.ST_CLEAN:
            raise SmiError(
                '%s object is already sealed' % self.__class__.__name__)

        else:
            self._additionalVarBinds.extend(varBinds)

        return self