class_docstr: As described in the MOCO paper, there is an extra BN layer
  following the res5 stage.
code: def __init__(self, cfg, input_shape):
      super().__init__(cfg, input_shape)
      norm = cfg.MODEL.RESNETS.NORM
      norm = get_norm(norm, self.res5[-1].out_channels)
      self.res5.add_module("norm", norm)
  
file_path: vissl/tools/object_detection_benchmark.py
imports: import os
  from detectron2.checkpoint import DetectionCheckpointer
  from detectron2.config import get_cfg
  from detectron2.engine import default_argument_parser, default_setup, DefaultTrainer, launch
  from detectron2.evaluation import COCOEvaluator, PascalVOCDetectionEvaluator
  from detectron2.layers import get_norm
  from detectron2.modeling.roi_heads import Res5ROIHeads, ROI_HEADS_REGISTRY
label_desc: Use image node_id 1 to create a new Res5ROIHeadsExtraNorm object from inherited base classes: Res5ROIHeads with example: obj = Res5ROIHeadsExtraNorm(cfg, input_shape)