docs: def move_selection(reverse=False):
      """
      Goes through the list of gunicorns, setting the selected as the one after
      the currently selected.
      """
      global selected_pid
      if selected_pid not in gunicorns:
          selected_pid = None
      found = False
      pids = sorted(gunicorns.keys(), reverse=reverse)
      # Iterate items twice to enable wrapping.
      for pid in pids + pids:
          if selected_pid is None or found:
              selected_pid = pid
              return
          found = pid == selected_pid