code: def maximize(self) -> 'Language':
          
          if self._filled is not None:
              return self._filled
  
          for broader in self.broaden():
              tag = broader.to_tag()
              if tag in LIKELY_SUBTAGS:
                  result = Language.get(LIKELY_SUBTAGS[tag], normalize=False)
                  result = result.update(self)
                  self._filled = result
                  return result
  
          raise RuntimeError(
              "Couldn't fill in likely values. This represents a problem with "
              "the LIKELY_SUBTAGS data."
          )
docs: The Unicode CLDR contains a "likelySubtags" data file, which can guess
          reasonable values for fields that are missing from a language tag.
  
          This is particularly useful for comparing, for example, "zh-Hant" and
          "zh-TW", two common language tags that say approximately the same thing
          via rather different information. (Using traditional Han characters is
          not the same as being in Taiwan, but each implies that the other is
          likely.)
  
          These implications are provided in the CLDR supplemental data, and are
          based on the likelihood of people using the language to transmit
          information on the Internet. (This is why the overall default is English,
          not Chinese.)
  
          >>> str(Language.get('zh-Hant').maximize())
          'zh-Hant-TW'
          >>> str(Language.get('zh-TW').maximize())
          'zh-Hant-TW'
          >>> str(Language.get('ja').maximize())
          'ja-Jpan-JP'
          >>> str(Language.get('pt').maximize())
          'pt-Latn-BR'
          >>> str(Language.get('und-Arab').maximize())
          'ar-Arab-EG'
          >>> str(Language.get('und-CH').maximize())
          'de-Latn-CH'
          >>> str(Language.make().maximize())    # 'MURICA.
          'en-Latn-US'
          >>> str(Language.get('und-ibe').maximize())
          'en-ibe-Latn-US'