What does Xiao Dezao mean by the phrase "A hole is full of autumn" in "The Story of Climbing Yueyang Tower"?

Middle school question 2b.

Climbing Yueyang Tower

Song? 6? 1 Xiao Dezao

If you don't leave, it's really a wandering trip.

Three-year-old guests, one autumn.

There is a saying that the heron flies to the end of the mountain.

I still don't think it's amazing, but I'm going to Yueyang Tower.

Deng Yueyang Tower (Xiao Dezao): It's a pity that I can't go to the five distant lakes by boat like Fan Li and swim Dongting Lake against my will. I have lived in Yelang for three years. This autumn, there is a boat floating on the lake. The place where the egret flew inspired me and became a poem; At the end of the day, as far as the eye can see, the faintly visible green hills stretch out. I don't think I have seen the most peculiar scenery, so I abandoned the boat and boarded Yueyang Tower!

[Teacher's Appreciation] Since the Tang Dynasty, there have been many poems about Yueyang Tower. Xiao Dezao's poem, like Lao Du's title, avoids the well-known place of climbing stairs to see the scenery. He only touched on the topic of climbing stairs in the last sentence. As for what he saw and felt when he climbed the stairs, there is no need to touch it. Readers can learn from predecessors' poems and associate freely, thus enriching the connotation of poems to the maximum extent. Smart and mature ideas are a new way. Write it down naturally all the way, and the aftertaste is not astringent. His deep feelings and wide artistic conception are amazing. (Han Bing)