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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 init_distributed(cuda):
 """ Initializes distributed backend. :param cuda: (bool) if True initializes nccl backend, if False initializes gloo backend """

    world_size = int(os.environ.get('WORLD_SIZE', 1))
    distributed = (world_size > 1)
    if distributed:
        backend = 'nccl' if cuda else 'gloo'
        dist.init_process_group(backend=backend,
                                init_method='env://')
        assert dist.is_initialized()
    return distributed