'Loads plugin-driver from configuration.'

def _load_drivers(self):

    LOG.info(_LI('Loading    Metering    driver    %s'), self.conf.driver)
    if (not self.conf.driver):
        raise SystemExit(_('A    metering    driver    must    be    specified'))
    self.metering_driver = driverutils.load_metering_driver(self, self.conf)
