stderr: ERROR: Could not find a version that satisfies the requirement fairscale==0.4.9 (from versions: 0.0.0, 0.0.1, 0.0.2, 0.0.3, 0.1.0, 0.1.1, 0.1.3, 0.1.4, 0.1.5, 0.1.6, 0.1.7, 0.3.0, 0.3.1, 0.3.2, 0.3.3, 0.3.4, 0.3.5, 0.3.6, 0.3.7, 0.3.8, 0.3.9, 0.4.0, 0.4.1, 0.4.2, 0.4.3, 0.4.4, 0.4.5, 0.4.6) ERROR: No matching distribution found for fairscale==0.4.9 

혹시 이런에러 본적있음??스택플로우에도 해결법이 없길래..