code: def test_shallow_cnn(self):
      model = ShallowCNN()
      model.init_weights()
      model.train()
  
      feat = model(self.imgs)
      self.assertEqual(feat.shape, torch.Size([1, 512, 8, 25]))
  
imports: import unittest
  import torch
  from mmocr.models.textrecog.backbones import ShallowCNN
label_desc: Use image node_id 2 for calling the TestShallowCNN obj's underlying member method code with example usage: obj.test_shallow_cnn() without return types