I tried it but it didn't work: You are using pip version 7.0.0, however version 21.2.2 is available. You should consider upgrading via the 'pip install --upgrade pip' command. Collecting twisted==0.7.0 Could not find a version that satisfies the requirement twisted==0.7.0 (from versions: 2.1.0, 9.0.0, 10.0.0, 10.1.0, 10.2.0, 11.0.0, 11.1.0, 12.0.0, 12.1.0, 12.2.0, 12.3.0, 13.0.0, 13.1.0, 13.2.0, 14.0.0, 14.0.1, 14.0.2, 15.0.0, 15.1.0, 15.2.0, 15.2.1, 15.3.0, 15.4.0, 15.5.0, 16.0.0, 16.1.0, 16.1.1, 16.2.0, 16.3.0, 16.3.1, 16.3.2, 16.4.0, 16.4.1, 16.5.0rc1, 16.5.0rc2, 16.5.0, 16.6.0rc1, 16.6.0, 16.7.0rc1, 16.7.0rc2, 17.1.0rc1, 17.1.0, 17.5.0, 17.9.0rc1, 17.9.0, 18.4.0rc1, 18.4.0, 18.7.0rc1, 18.7.0rc2, 18.7.0, 18.9.0rc1, 18.9.0, 19.2.0rc1, 19.2.0rc2, 19.2.0, 19.2.1, 19.7.0rc1, 19.7.0, 19.10.0rc1, 19.10.0, 20.3.0rc1, 20.3.0, 21.2.0rc1, 21.2.0, 21.7.0rc1, 21.7.0rc2, 21.7.0rc3, 21.7.0) No matching distribution found for twisted==0.7.0