class_docstr: Base class for tracked locals and stack values
  
  VariableTracker instances are immutable and should be copied in
  order to change them.
class_docstr_tok: ["Base","class","for","tracked","locals","and","stack","values","VariableTracker","instances","are","immutable","and","should","be","copied","in","order","to","change","them","."]
docstr: Deeper (but not full) copy, leaving FX and user objects alone
docstr_tok: ["Deeper","(","but","not","full",")","copy",",","leaving","FX","and","user","objects","alone"]
code: def copy(cls, value):
      """Deeper (but not full) copy, leaving FX and user objects alone"""
      return cls.apply(identity, value)
  
imports: import collections
  from enum import Enum
  from typing import Any, Callable, Dict, List
  from ..None import variables
  from ..current_scope_id import current_scope_id
  from ..exc import unimplemented
  from ..source import AttrSource, Source
  from ..utils import identity, istype
label_desc: Use image node_id 2 for calling the VariableTracker obj's underlying member method code with example usage: obj.copy(cls, value) and returns: cls