code: def __init__(self, dist_func: DistanceFunc | FunctionWrapper):
      self.dist_func = dist_func
  
file_path: river/river/neighbors/base.py
imports: from __future__ import annotations
  import abc
  import typing
  from river import base
label_desc: Use image node_id 1 to create a new BaseNN object from inherited base classes: base, abc with example: obj = BaseNN(dist_func)