code: func (r *DrvRegistry) Driver(name string) (driverapi.Driver, *driverapi.Capability) {
  	r.Lock()
  	defer r.Unlock()
  
  	d, ok := r.drivers[name]
  	if !ok {
  		return nil, nil
  	}
  
  	return d.driver, &d.capability
  }
docs: // Driver returns the actual network driver instance and its capability  which registered with the passed name.