code: def setUp(self) -> None:
      self.db_head = DBHead(
          in_channels=10,
          module_loss=dict(type="DBDummy"),
          postprocessor=dict(type="DBDummy"),
      )
  
file_path: mmocr/tests/test_models/test_textdet/test_heads/test_db_head.py
imports: from unittest import TestCase
  import torch
  from mmocr.models.textdet.heads import DBHead
  from mmocr.registry import MODELS
label_desc: Use image node_id 1 for calling the TestDBHead obj's underlying member method code with example usage: obj.setUp() without return types