class_docstr: Bbox head used in Double-Head R-CNN
  
  .. code-block:: none
  
                                        /-> cls
                    /-> shared convs ->
                                        \-> reg
      roi features
                                        /-> cls
                    \-> shared fc    ->
                                        \-> reg
docstr: Add the fc branch which consists of a sequential of conv layers.
docstr_tok: ["Add","the","fc","branch","which","consists","of","a","sequential","of","conv","layers","."]
code: def _add_conv_branch(self):
      """Add the fc branch which consists of a sequential of conv layers."""
      branch_convs = nn.ModuleList()
      for i in range(self.num_convs):
          branch_convs.append(
              Bottleneck(
                  inplanes=self.conv_out_channels,
                  planes=self.conv_out_channels // 4,
                  conv_cfg=self.conv_cfg,
                  norm_cfg=self.norm_cfg,
              )
          )
      return branch_convs
  
file_path: insightface/detection/scrfd/mmdet/models/roi_heads/bbox_heads/double_bbox_head.py
imports: import torch.nn
  from mmcv.cnn import ConvModule, normal_init, xavier_init
  from mmdet.models.backbones.resnet import Bottleneck
  from mmdet.models.builder import HEADS
  from .bbox_head import BBoxHead
label_desc: Use image node_id 2 for calling the DoubleConvFCBBoxHead obj's underlying member method code with example usage: obj._add_conv_branch() and returns: branch_convs