code: def search(self, buf):
          
          self._check_type(buf)
          best_match = None
          best_index = sys.maxsize
          for searcher in self:
              match = searcher.search(buf)
              if match and match.start < best_index:
                  best_match = match
                  best_index = match.start
          return best_match
docs: Search the provided buffer for a match to any sub-searchers.
  
          Search the provided buffer for a match to any of this collection's
          sub-searchers. If a single matching sub-searcher is found, returns that
          sub-searcher's *match* object. If multiple matches are found, the match
          with the smallest index is returned. If no matches are found, returns
          ``None``.
  
          :param buf: Buffer to search for a match.
          :return: :class:`RegexMatch` if matched, None if no match was found.