def _all_reduce_dict()

in detector/train.py [0:0]


def _all_reduce_dict(d, device):
    # wrap in tensor and use reduce to gpu0 tensor
    output_d = {}
    for (key, value) in sorted(d.items()):
        tensor_input = torch.tensor([[value]]).to(device)
        torch.distributed.all_reduce(tensor_input)
        output_d[key] = tensor_input.item()
    return output_d