func (s *Server) Close() {
	s.mu.Lock()
	defer s.mu.Unlock()
	s.closed.Set()
	s.socket.Close()
}
func (s *Server) Close() {
	s.mu.Lock()
	defer s.mu.Unlock()
	s.closed.Set()
	s.socket.Close()
}
// Stops the server network activity. This is all that's required to clean-up a Server.