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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 unregister(self, fd):
 """ Unregister an USB-unrelated fd from poller. Convenience method. """

        if fd in self.__fd_set:
            raise ValueError(
                'This fd is a special USB event fd, it must stay registered.'
            )
        self.__poller.unregister(fd)