code: def obfuscate_unique(tokens, index, replace, replacement, *args):
      
      def return_replacement(replacement):
          UNIQUE_REPLACEMENTS[replacement] = replace
          return replacement
      tok = tokens[index]
      token_type = tok[0]
      token_string = tok[1]
      if token_type != tokenize.NAME:
          return None # Skip this token
      if token_string == replace:
          return return_replacement(replacement)
docs: If the token string (a unique value anywhere) inside *tokens[index]*
      matches *replace*, return *replacement*.
  
      .. note::
  
          This function is only for replacing absolutely unique ocurrences of
          *replace* (where we don't have to worry about their position).