code: function Subgraph() {
          var that = this;
          this.size = [140, 80];
          this.properties = { enabled: true };
          this.enabled = true;
  
          //create inner graph
          this.subgraph = new LGraph();
          this.subgraph._subgraph_node = this;
          this.subgraph._is_subgraph = true;
  
          this.subgraph.onTrigger = this.onSubgraphTrigger.bind(this);
  
          this.subgraph.onInputAdded = this.onSubgraphNewInput.bind(this);
          this.subgraph.onInputRenamed = this.onSubgraphRenamedInput.bind(this);
          this.subgraph.onInputTypeChanged = this.onSubgraphTypeChangeInput.bind(
              this
          );
          this.subgraph.onInputRemoved = this.onSubgraphRemovedInput.bind(this);
  
          this.subgraph.onOutputAdded = this.onSubgraphNewOutput.bind(this);
          this.subgraph.onOutputRenamed = this.onSubgraphRenamedOutput.bind(this);
          this.subgraph.onOutputTypeChanged = this.onSubgraphTypeChangeOutput.bind(
              this
          );
          this.subgraph.onOutputRemoved = this.onSubgraphRemovedOutput.bind(this);
      }
docs: Subgraph: a node that contains a graph