code: def __init__(self):
      super().__init__()
      self.linear1 = torch.nn.Linear(4, 4)
      self.linear2 = torch.nn.Linear(4, 4)
  
file_path: colossalai/tests/test_fx/test_tracer/test_activation_checkpoint_annotation.py
imports: import torch
  from torch.fx import GraphModule
  from torch.utils.checkpoint import checkpoint
  from colossalai.fx import ColoTracer
  from colossalai.testing import clear_cache_before_run
label_desc: Use image node_id 1 to create a new MLP object from inherited base classes: torch.nn with example: obj = MLP()