code: def _find(self, index):
          
          match = _PATTERN.search(self.text, index)
          while self._max_tries > 0 and match is not None:
              start = match.start()
              candidate = self.text[start:match.end()]
  
              # Check for extra numbers at the end.
              # TODO: This is the place to start when trying to support
              # extraction of multiple phone number from split notations (+41 79
              # 123 45 67 / 68).
              candidate = self._trim_after_first_match(_SECOND_NUMBER_START_PATTERN,
                                                       candidate)
  
              match = self._extract_match(candidate, start)
              if match is not None:
                  return match
              # Move along
              index = start + len(candidate)
              self._max_tries -= 1
              match = _PATTERN.search(self.text, index)
          return None
docs: Attempts to find the next subsequence in the searched sequence on or after index
          that represents a phone number. Returns the next match, None if none was found.
  
          Arguments:
          index -- The search index to start searching at.
          Returns the phone number match found, None if none can be found.