What time did it get dark in Lanzhou on June 19, 2002?

Dark time: 20:54:37. Lanzhou, referred to as "Lan" and "Gao", was called Jincheng in ancient times. It is a prefecture-level city and provincial capital under the jurisdiction of Gansu Province, and a type II big city [9 1]. It is an important industrial base and comprehensive transportation hub in the northwest of China, one of the important central cities in the western region approved by the State Council and an important node city in the Silk Road Economic Belt.