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Flann O'Brien, the renowned Irish writer and satirist, passed away on 1 April 1966 at the age of 53. He left behind a lasting legacy in the literary world with his iconic works, including "At Swim-Two-Birds" and "The Third Policeman," which continue to entertain and captivate readers to this day. O'Brien's unique blend of humor, satire, and philosophical exploration has cemented his position as one of Ireland's most celebrated writers.