code: def active_language(self):
          
          # Current instance language (if user uses activate_language() method)
          if self._language is not None:
              return self._language
  
          # Current site language (translation.get_language())
          current = utils.get_language()
          if current in self.supported_languages:
              return current
  
          # Default language descriptor
          return self.default_language
docs: Returns active language.