code: func (n *Node) doRaftSnapshot(conn redcon.Conn, cmd redcon.Command) (interface{}, error) {
  	if len(cmd.Args) != 1 {
  		return nil, ErrWrongNumberOfArguments
  	}
  	f := n.raft.Snapshot()
  	err := f.Error()
  	if err != nil {
  		conn.WriteError("ERR " + err.Error())
  		return nil, nil
  	}
  	conn.WriteString("OK")
  	return nil, nil
  }
docs: // doRaftSnapshot handles a "RAFTSNAPSHOT" client command.