I want to know the answer to the following question:
What year was Qiantang raised in status and renamed Hangzhou?
All the background I'm provided with is that "Despite the continuing prominence of Nanjing (then known as Jiankang), the settlement of Qiantang, the former name of Hangzhou, remained one of the three major metropolitan centers in the south to provide major tax revenue to the imperial centers in the north China.". Is that enough to answer the question?