What is the writing background of Chun Yan?

Zhang Shengping. According to relevant information, the writing background of this poem is related to Zhang's life and the background of the times. Chun Yan is a seven-character quatrain written by Tang Dynasty poet Zhang, in which "Chun Yan" refers to the scene of swallows flying on the water in spring. This poem is one of Zhang's representative works, and it is known as "the swan song of the ages".