text: #include "caffe2/operators/utility_ops.h"
  
  namespace caffe2 {
  
  REGISTER_CPU_OPERATOR(Sum, SumOp<CPUContext>);
  
  OPERATOR_SCHEMA(Sum)
      .NumInputs(1, INT_MAX)
      .NumOutputs(1)
      .AllowInplace({{0, 0}})
      .InputsCanCrossDevices()
      .IdenticalTypeAndShapeOfInput(0)
      .SetDoc(R"DOC(
  Element-wise sum of each of the input tensors. The first input tensor can be
  used in-place as the output tensor, in which case the sum will be done in
  place and results will be accumulated in input0. All inputs and outputs must
  have the same shape and data type.
  )DOC")
      .Input(0, "data_0", "First of the input tensors. Can be inplace.")
      .Output(0, "sum", "Output tensor. Same dimension as inputs.");
  }
  