code: def _extract_match(self, candidate, offset):
          
          # Skip a match that is more likely a publication page reference or a
          # date.
          if (_SLASH_SEPARATED_DATES.search(candidate)):
              return None
  
          # Skip potential time-stamps.
          if _TIME_STAMPS.search(candidate):
              following_text = self.text[offset + len(candidate):]
              if _TIME_STAMPS_SUFFIX.match(following_text):
                  return None
  
          # Try to come up with a valid match given the entire candidate.
          match = self._parse_and_verify(candidate, offset)
          if match is not None:
              return match
  
          # If that failed, try to find an "inner match" -- there might be a
          # phone number within this candidate.
          return self._extract_inner_match(candidate, offset)
docs: Attempts to extract a match from a candidate string.
  
          Arguments:
          candidate -- The candidate text that might contain a phone number.
          offset -- The offset of candidate within self.text
          Returns the match found, None if none can be found