157051
In 398 , during the reign of Emperor An , Pei 's uncle Yu Kai ( 庾楷 ) , who was the Governor of Yu Province , allied with Wang Gong ( 王恭 ) , the Governor of Yan and Qing provinces , to attack the imperial capital of Jiankang .
 Emperor An, Pei, Yu, Yu, Jiankang
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Emperor An, Pei, Yu, Yu, Jiankang