code: def quality_to_apply(self):
          
          if (self.request.quality is None):
              if (self.api_version <= '1.1'):
                  return('native')
              else:
                  return('default')
          return(self.request.quality)
docs: Value of quality parameter to use in processing request.
  
          Simple substitution of 'native' or 'default' if no quality
          parameter is specified.