What does Zhang Songyuan mean by writing Bashu Danqing?

It reflects some cultural phenomena in ancient China, such as accommodating human feelings and vanity. Bashu Danqing Zhang Songyuan's Crazy Ghost is a short story in the novel Ancient and Modern Jokes by Feng Menglong, a writer in Ming Dynasty. The story is mainly about a painter named Zhang Songyuan. He often gets drunk while painting, and then fantasizes that he is a fairy. The portraits he draws are also very surprising. One day, he was kicked out of the pub because he was drunk and met a fool on the way. After hearing that Zhang Songyuan was a painter, the fool borrowed a brush from him and drew a figure painting, but it was ugly. After reading it, Zhang Songyuan spoke highly of the characters he painted, calling them "Bashu Danqing". The fool was satisfied with this and asked Zhang Songyuan to draw more figure paintings.