code: def has_node(self, n: NodeKey) -> bool:
      return n in self
  
imports: from __future__ import annotations
  import operator
  from copy import deepcopy
  from typing import TYPE_CHECKING
  import cupy
  import networkx
  import numpy
  import pylibcugraph
  import nx_cugraph
  from ..utils import index_dtype
label_desc: Use image node_id 26 for calling the Graph obj's underlying member method code with example usage: obj.has_node(n) and returns: unknown