Status GraphDefImporter::ConvertNodeDef(OpBuilder &builder, ConversionState &s,
                    const NodeDef &node) {
 VLOG(4) << "Importing: " << node.name();
 OperationState state(ConvertLocation(node), absl::StrCat("tfg.", node.op()));

 // The GraphImporter does light shape inference, but here we will defer all of
 // that to the shape inference pass.
 const OpDef *op def;
 const OpRegistrationData *op reg data = nullptr;
 if ((op reg data = registry .LookUp(node.op()))) {
  op def = &op reg data->op def;
 } else {
  auto it = function op defs .find(node.op());
  if (it == function op defs .end())
   return InvalidArgument("Unable to find OpDef for ", node.op());
  op def = it->second;
 }