The political sense traces to March 1949, when Mao Zedong told comrades as they left Xibaipo for Beijing: '
今天是进京赶考的日子' ('today we're going to the capital to sit the exam'), meaning taking power was itself an exam history would grade. Xi Jinping revived the metaphor around the CCP's 100th anniversary in 2021. Named a 2021 Top 10 buzzword by 《
咬文嚼字》.