code: def _expand(node: Node) -> None:
      if not node:
          node[:] = [], [], None
  
imports: import collections
  from typing import Any, Callable, Deque, Generic, List, Optional, Sequence, Tuple, TypeVar
  import numpy
  from pfrl.utils.random import sample_n_k
label_desc: Use image node_id 1 for calling a global function with example usage: _expand(node) without return types