code: def retrieveVals(self):
          
          apacheInfo = ApacheInfo(self._host, self._port,
                                  self._user, self._password, 
                                  self._statuspath, self._ssl)
          stats = apacheInfo.getServerStats()
          if self.hasGraph('apache_access'):
              self.setGraphVal('apache_access', 'reqs', stats['Total Accesses'])
          if self.hasGraph('apache_bytes'):
              self.setGraphVal('apache_bytes', 'bytes', 
                               stats['Total kBytes'] * 1000)
          if self.hasGraph('apache_workers'):
              self.setGraphVal('apache_workers', 'busy', stats['BusyWorkers'])
              self.setGraphVal('apache_workers', 'idle', stats['IdleWorkers'])
              self.setGraphVal('apache_workers', 'max', stats['MaxWorkers'])
docs: Retrieve values for graphs.