Python2 to 3: migration and the improvement of the WMAgentScripts repository for CMS Computing Operations

The Compact Muon Solenoid (CMS) experiment consists in a multi-purpose detector located at the Large Hadron Collider (LHC), at CERN. It collects data from collisions occurring every 25ns during an LHC run. However, even in a long shutdown period, a huge amount of events is still processed and analyzed by the CMS experiment. It reaches around 2PB per month — if considered collision data and Monte Carlo simulations. Hence, the CMS production is continuously running hundreds of thousands of jobs in the Worldwide LHC Computing Grid (WLCG) [1], using up to 300k of the available processor cores.