python的f-string问题

Question

u = 'https://xxx.com/{id}'
id = 1
b = f"{u}" #'https://xxx.com/{id}'
c = 'https://xxx.com/1'

python的f-string怎么做到让b达到c的结果？不能先定义id，也不想要f'{xxx.com}{id}'的方法，主要想知道有没有什么奇技淫巧。

Answer 1

u = 'https://xxx.com/{id}'
id = 1
c = u.format(id = id)