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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 orb(self):
        '''The ORB used to access this object.

        This property's value will be None if no object above this object is a
        name server.

        '''
        with self._mutex:
            if self._parent.name == '/':
                return None
            return self._parent.orb