code: func (p *Pubring) Get(id string) *PublicKey {
  	p.Lock()
  	defer p.Unlock()
  
  	xpk := p.fetch(id)
  	if xpk == nil {
  		if p.secring != nil {
  			if pk := p.secring.Get(id); pk != nil {
  				return &pk.PublicKey
  			}
  		}
  		return nil
  	}
  
  	return pubPBToKR(xpk)
  }
docs: // Get returns a single key