code: func NewDriver(machineName, storePath string) drivers.Driver {
  	log.Debug("Instantiating Rackspace driver.", map[string]string{"machineName": machineName})
  
  	inner := openstack.NewDerivedDriver(machineName, storePath)
  	driver := &Driver{
  		Driver: inner,
  	}
  	inner.SetClient(&Client{
  		driver: driver,
  	})
  
  	return driver
  }
docs: // NewDriver instantiates a Rackspace driver.