docs: def set_gid(self):
          """Change the group of the running process"""
          if self.group:
              gid = getgrnam(self.group).gr_gid
              try:
                  os.setgid(gid)
              except Exception:
                  message = ("Unable to switch ownership to {0}:{1}. " +
                             "Did you start the daemon as root?")
                  print(message.format(self.user, self.group))
                  sys.exit(1)