This poem is actually a Tibetan poem. Look at this Tibetan poem, which can be simply understood as a poem for Hui Ling.
Poetry is a lyrical literary genre. Mao's Preface to Poetry says: "Poets have their own aspirations. Have ambition in your heart and speak like a poem. " Yan Yu's Poems on Canglang in the Southern Song Dynasty said that "poets chant temperament". There is only one art expressed in words: poetry.
In ancient China, unhappy people were called poems and happy people were called songs. In modern times, they are generally called poems. It expresses social life and people's spiritual world according to certain syllables and rhythms.