code: def forward(self, feat):
      out = self.shortcut(feat)
      return out
  
imports: import paddle
  import paddle.nn
  import paddle.nn.functional
  from paddle import ParamAttr
  from paddle.nn.initializer import Constant, Uniform, Normal, XavierUniform
  from ppdet.core.workspace import register, serializable
  from paddle.regularizer import L2Decay
  from ppdet.modeling.layers import DeformableConvV2, ConvNormLayer, LiteConv
  import math
  from ppdet.modeling.ops import batch_norm
  from ..shape_spec import ShapeSpec
label_desc: Use image node_id 2 for calling the ShortCut obj's underlying member method code with example usage: obj.forward(feat) and returns: out