code: func FreePixmap(X *xgbutil.XUtil, pixid xproto.Pixmap) {
  	xproto.FreePixmap(X.Conn(), pixid)
  }
docs: // FreePixmap is a convenience function for destroying a pixmap resource
  // on the X server.
  // If you're using an xgraphics.Image value, then its Destroy method will call
  // this for you.