How many distinct stages were there in Germany's 1. Bundesliga during the 2015/2016 season?

How many distinct stages were there in Germany's 1. Bundesliga during the 2015/2016 season?: a task in SmolDataEnvs-harbor-train-sandbox: 📊 SmolDataEnvs: Harbor (train) (Harbor dataset). Files (in /home/user/input, no subfolders): - database.sqlite