Seek the full text of this philosophical poem "Not necessarily"

You cannot change the environment, but you can change yourself; You can't change the facts, but you can change your attitude; You cannot change the past, but you can change the present; You can't control others, but you can control yourself; You can't predict tomorrow, but you can grasp today; You can't do everything smoothly, but you can do everything wholeheartedly; You can't control the weather, but you can change your mood; You can't choose your appearance, but you can smile; You can't extend the length of life, but you can decide the width of life; If we look at the world with a pair of "eyes", we will be less sad and worried and more happy.