docs: def find_whole_word(w):
      """
      Scan through string looking for a location where this word produces a match,
      and return a corresponding MatchObject instance.
      Return None if no position in the string matches the pattern;
      note that this is different from finding a zero-length match at some point in the string.
      """
      return re.compile(r'\b({0})\b'.format(w), flags=re.IGNORECASE).search