code: def getPyCmd(cls):
          
          if "win32" in sys.platform:
              return 'py'
          elif "linux" in sys.platform:
              return 'python3'
          elif 'darwin' in sys.platform:
              return 'python3'
          else:
              cit.err("No python3 command for " + sys.platform)
docs: get OS's python command