root_peer_list.go
func (l *RootPeerList) Get(hostPort string) (*Peer, bool) {
	l.RLock()
	p, ok := l.peersByHostPort[hostPort]
	l.RUnlock()
	return p, ok
}
func (l *RootPeerList) Get(hostPort string) (*Peer, bool) {
	l.RLock()
	p, ok := l.peersByHostPort[hostPort]
	l.RUnlock()
	return p, ok
}
// Get returns a peer for the given hostPort if it exists.