code: def __init__(self) -> None:
      self.children: Dict[int, TreeNode] = defaultdict(TreeNode)
      self.live_child_count: "Optional[int]" = None
      self.n: "Optional[int]" = None
  
file_path: catboost/contrib/python/hypothesis/py3/hypothesis/internal/conjecture/choicetree.py
imports: from collections import defaultdict
  from random import Random
  from typing import Callable, Dict, Iterable, List, Optional, Sequence
  from hypothesis.internal.conjecture.junkdrawer import LazySequenceCopy, pop_random
label_desc: Use image node_id 1 to create a new TreeNode object  with example: obj = TreeNode()