The sun in the sky is red. What year was this song written?

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In the program "Revolutionaries are always young" in the literary evening to commemorate the 80th anniversary of the founding of the Party, a song "The sun in the sky is red" attracted a wide audience. The author of this song is Sean Song, a musician who once worked in Changsha. Sean Song, a native of Hanchuan, Hubei Province, participated in the Anti-Japanese Drama Troupe during the War of Resistance against Japanese Aggression period. After the victory of the Anti-Japanese War, he taught music at Zuojialong Tsinghua Middle School in Hexi, Changsha. His songs, such as "The Sun is Red in the Sky", "Bamboo is Easy to Bend" and "Couples Singing", were widely circulated among students and young people at that time. 1In August, 949, Hunan was peacefully liberated, and Changsha established the Workers' Art Troupe, headed by him. At this time, another musician, Jerry Liau, who wrote "Song of the Boatman in Yuanjiang" during the Anti-Japanese War, also came to Changsha and joined the Municipal Workers' Art Troupe. Sean Song asked Jerry Liau to compose the long-standing Red Sun in the Sky into four harmonies to make the song more perfect. 1953 This song won the second prize of the National Pop Song Award for three years. Sean Song and Jerry Liau are two musicians who are a perfect match. At that time, it was called "Yang Er" by Hunan music circle. 1952 after the reorganization of Hunan provincial art troupe, Sean Song and Jerry Liau both worked in the music studio of Hunan provincial cultural bureau, with Song Yang as the team leader. Soon, he was transferred to Beijing. He first worked in China Conservatory of Music, then served as the deputy editor of Song magazine, and has lived in Beijing since his retirement. Jerry Liau has been working in Changsha, 1987 retired from the Provincial Art College. I looked for a lot, but I couldn't find the exact time. It is estimated that this song should have existed before 1950.