成功的关键是专注于目标，而不是障碍。
The key to success is to focus on goals, not obstacles.
The only limit is the one you set yourself.
It's not supposed to be easy.Anyone who finds it easy is stupid.
一个好的模型是准确性和简洁性之间的折衷。
预测未来的最好方法就是发明它。