code: def __init__(self, out_channels, use_bn=True):
      super(stem, self).__init__()
      if use_bn:
          self.net = nn.Sequential(
              nn.Conv2d(
                  in_channels=3,
                  out_channels=out_channels,
                  kernel_size=3,
                  padding=1,
                  bias=False,
              ),
              nn.BatchNorm2d(out_channels),
          )
      else:
          self.net = nn.Sequential(
              nn.Conv2d(
                  in_channels=3,
                  out_channels=out_channels,
                  kernel_size=3,
                  padding=1,
                  bias=False,
              )
          )
  
imports: import torch.nn
label_desc: Use image node_id 1 to create a new stem object from inherited base classes: nn with example: obj = stem(out_channels, use_bn)