code: def link(self, another: "GraphNode"):
      self.links.add(another)
      another.links.add(self)
  
imports: from typing import List, Set
  import torch
  from stanza.models.coref.const import EPSILON
label_desc: Use image node_id 2 for calling the GraphNode obj's underlying member method code with example usage: obj.link(another) without return types