code: func (r *DrvRegistry) IPAM(name string) (ipamapi.Ipam, *ipamapi.Capability) {
  	r.Lock()
  	defer r.Unlock()
  
  	i, ok := r.ipamDrivers[name]
  	if !ok {
  		return nil, nil
  	}
  
  	return i.driver, i.capability
  }
docs: // IPAM returns the actual IPAM driver instance and its capability which registered with the passed name.