code: def init_weight(self):
      if self.pretrained is not None:
          ppmatting.utils.load_pretrained_model(self, self.pretrained)
  
imports: import paddle
  from paddle import ParamAttr
  import paddle.nn
  import paddle.nn.functional
  from paddle.nn import Conv2D, BatchNorm, Linear, Dropout
  from paddle.nn import AdaptiveAvgPool2D, MaxPool2D, AvgPool2D
  from paddleseg.cvlibs import manager
  import ppmatting
label_desc: Use image node_id 3 for calling the VGGNet obj's underlying member method code with example usage: obj.init_weight() without return types