''The city had many nicknames: Gotham. Metropolis. The shining Starr. The big apple. The city that never sleeps. These nicknames were not always accurate. For example, why would anyone refer to a city as an overlarge piece of fruit? also the city did sleep, but it slept the way a cat does, eyes half open, watchful, ready to spring at the first sign of fun, or danger.''
What does the author compare the city with?