tflite::BuiltinOperator builtin) {
  auto it = opcode_index_map_.insert({op_name, 0});

  // If the insert succeeded, the opcode has not been created already. Create a
  // new operator code and update its index value in the map.
  if (it.second) {
    it.first->second = opcodes_.size();
    auto custom_code = builtin == tflite::BuiltinOperator_CUSTOM

  return UnrankedTensorType::get(element_type);
}

// Returns true if the op creates a TensorList.
bool IsTensorListInitOp(Operation* op) {
  return isa<TensorListReserveOp>(op) || isa<EmptyTensorListOp>(op) ||
         isa<TensorListFromTensorOp>(op);
}

// Returns the `element_shape` operand of the ops that create a TensorList.
Value GetElementShapeOperand(Operation* op) {