code: def draw_annotation(img, boxes, klass, is_crowd=None):
      
      labels = []
      assert len(boxes) == len(klass)
      if is_crowd is not None:
          assert len(boxes) == len(is_crowd)
          for cls, crd in zip(klass, is_crowd):
              clsname = cfg.DATA.CLASS_NAMES[cls]
              if crd == 1:
                  clsname += ';Crowd'
              labels.append(clsname)
      else:
          for cls in klass:
              labels.append(cfg.DATA.CLASS_NAMES[cls])
      img = viz.draw_boxes(img, boxes, labels)
      return img
docs: Will not modify img