code: func (pn *peernet) ClosePeer(p peer.ID) error {
  	pn.RLock()
  	cs, found := pn.connsByPeer[p]
  	if !found {
  		pn.RUnlock()
  		return nil
  	}
  
  	var conns []*conn
  	for c := range cs {
  		conns = append(conns, c)
  	}
  	pn.RUnlock()
  	for _, c := range conns {
  		c.Close()
  	}
  	return nil
  }
docs: // ClosePeer connections to peer