code: def test_single_geom_conversion(self):
      rects = Rectangles([(0, 0, 1, 1)])
      geom = rects.geom()
      self.assertIsInstance(geom, Polygon)
      self.assertEqual(
          np.array(geom.exterior.coords),
          np.array(
              [
                  [1.0, 0.0],
                  [1.0, 1.0],
                  [0.0, 1.0],
                  [0.0, 0.0],
                  [1.0, 0.0],
              ]
          ),
      )
  
imports: import numpy
  from holoviews.element.comparison import ComparisonTestCase
  from shapely.geometry import GeometryCollection, Polygon, Point, LineString, LinearRing, MultiPolygon, MultiLineString, MultiPoint
  from geoviews.element import Rectangles, Path, Polygons, Points, Segments
label_desc: Use image node_id 2 for calling the TestRectangles obj's underlying member method code with example usage: obj.test_single_geom_conversion() without return types