 the node data object via data binding
          geometryString: 'F1 M0 0 L20 0 20 20 0 20 z',
          fill: 'rgba(128, 128, 128, 0.5)'
        })
          // this determines the actual shape of the Shape
          .bind('geometryString', 'geo')
          // selection causes the stroke to be blue instead of black
          .bindObject('stroke', 'isSelected', (s) => (s ? 'dodgerblue' : 'black'))
      );

    // Show different kinds of port fittings by using different shapes in this Binding converter
    