code: func (p *multiResourcePool) NumActive() int32 {
  	total := int32(0)
  
  	p.rwMutex.RLock()
  	defer p.rwMutex.RUnlock()
  
  	for _, pool := range p.locationPools {
  		total += pool.NumActive()
  	}
  	return total
  }
docs: // See ResourcePool for documentation.