code: def addarc(
      self, next: "NFAState", label: Optional[str] = None
  ) -> None:
      assert label is None or isinstance(label, str)
      assert isinstance(next, NFAState)
      self.arcs.append((label, next))
  
imports: import os
  from typing import IO, Any, Dict, Iterator, List, NoReturn, Optional, Sequence, Tuple, Union
  from blib2to3.pgen2 import grammar, token, tokenize
  from blib2to3.pgen2.tokenize import GoodTokenInfo
label_desc: Use image node_id 2 for calling the NFAState obj's underlying member method code with example usage: obj.addarc(next, label) without return types