code: def node(self):
      # the node for attributes is added lazily, since most will just be method calls
      # which do not rely on the getitem call
      if self._node is None:
          self._node = self.tracer.create_proxy(
              "call_function", getattr, (self.root, self.attr), {}
          ).node
      return self._node
  
imports: import operator
  from typing import Any, Callable, Dict, Optional, Union
  import torch
  from torch.fx import Node, Proxy
  from torch.utils._pytree import tree_map
  from colossalai._analyzer._subclasses import MetaTensor
label_desc: Use image node_id 2 for calling the ColoAttribute obj's underlying member method code with example usage: obj.node() and returns: self