code: func filterTargets(peers []fab.Peer, filter fab.TargetFilter) []fab.Peer {
  
  	if filter == nil {
  		return peers
  	}
  
  	filteredPeers := []fab.Peer{}
  	for _, peer := range peers {
  		if filter.Accept(peer) {
  			filteredPeers = append(filteredPeers, peer)
  		}
  	}
  
  	return filteredPeers
  }
docs: // filterTargets is helper method to filter peers