What is the theme song of the Monkey King?

Four brothers, all southerners, came to work in the north. The boss sells train shafts (referred to as fire shafts), the second sells steamed bread, the third sells cabbage, and the fourth buys pot covers.

One day, four brothers were hawking in the market. Boss: The fire shaft caught fire, but then he asked if he was alive. Second child: steamed bread (south end), fire fighters rushed south and didn't see the fire; Old three: cabbage (white) fire fighter still didn't understand; Old four: The pot cover (deserved it).