How to use the geojs/annotation.polygonAnnotation function in geojs

y: coordinates[1]
        },
        style
      }));
    } else if (type === 'rectangle') {
      annotation_layer.addAnnotation(rectangleAnnotation({
        corners: _.map(coordinates[0], (coords) => {
          return {
            x: coords[0],
            y: coords[1]
          };
        }),
        style
      }));
    } else if (type === 'polygon') {
      annotation_layer.addAnnotation(polygonAnnotation({
        vertices: _.map(coordinates[0], (coords) => {
          return {
            x: coords[0],
            y: coords[1]
          };
        }),
        style
      }));
    } else {
      console.error('Attempting to add annotation of type ' + type);
      return false;
    }
    annotation_layer.geoOff(geo_event.annotation.add, _handler);

    if (!annotation) {
      console.error('GeoJS did not respond with a synchronous annotation event.');