}

def TF_CollectivePermuteOp : TF_Op<"CollectivePermute", []> {
  let summary = "An Op to permute tensors across replicated TPU instances.";

  let description = [{
Each instance supplies its own input.

For example, suppose there are 4 TPU instances: `[A, B, C, D]`. Passing
source_target_pairs=`[[0,1],[1,2],[2,3],[3,0]]` gets the outputs:
`[D, A, B, C]`.
  }];

  let arguments = (ins