code: def eval(self):
      self.training = False
      for layer in self.sublayers():
          layer.training = False
          layer.eval()
  
imports: import os
  from typing import Union
  import paddle
  import paddle.nn
  import paddlehub.vision.transforms
  import numpy
  from paddlehub.module.module import moduleinfo
  from paddlehub.module.cv_module import ImageClassifierModule
label_desc: Use image node_id 3 for calling the RepVGG_B2G4 obj's underlying member method code with example usage: obj.eval() without return types