}

  if (n->type_string() != "AssignAddVariableOp" &&
      n->type_string() != "AssignSubVariableOp") {
    return false;
  }

  DataType dtype;
  if (!TryGetNodeAttr(n->def(), "dtype", &dtype) || !DataTypeIsInteger(dtype)) {
    return false;
  }

  Node* const_input = nullptr;
  for (const Edge* e : n->in_edges()) {
    if (!e->IsControlEdge() && e->src()->IsConstant()) {
      const_input = e->src();