# 19.6 Extension modules

`stdwin`
  -- Interface to STDWIN (an old, unsupported platform-independent GUI package). Obsolete; use `Tkinter` for a platform-independent GUI instead.

The following are SGI specific, and may be out of touch with the current version of reality.

`cl`
  -- Interface to the SGI compression library.

`sv`
  -- Interface to the ``simple video'' board on SGI Indigo (obsolete hardware).