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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 pack(self):
        '''
        Pack this exception into a serializable dictionary that is safe for
        transport via msgpack
        '''
        if six.PY3:
            return {'message': six.text_type(self), 'args': self.args}
        return dict(message=self.__unicode__(), args=self.args)