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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 barrier():
 """ Works as a temporary distributed barrier, currently pytorch doesn't implement barrier for NCCL backend. Calls all_reduce on dummy tensor and synchronizes with GPU. """

    if torch.distributed.is_available() and torch.distributed.is_initialized():
        torch.distributed.all_reduce(torch.cuda.FloatTensor(1))
        torch.cuda.synchronize()