code: def _shortcut(str1: str, str2: str) -> Optional[float]:
      if not str1 and not str2:
          return 0.0
      elif str1 == str2:
          return 1.0
      else:
          return None
  
file_path: textacy/src/textacy/similarity/edits.py
imports: from __future__ import annotations
  from typing import Optional
  import sklearn.feature_extraction
  import sklearn.metrics
  from jellyfish import hamming_distance
  from jellyfish import jaro_similarity
  from jellyfish import levenshtein_distance
  from ..None import constants
label_desc: Use image node_id 1 for calling a global function with example usage: _shortcut(str1, str2) and returns: int, int, None