-#! /usr/bin/env python
+#! /usr/bin/env python3
"""print(background filename)
print(the filename of the current or previous background image.)
filename = xsetbg_db.select('last_shown IS NOT NULL',
orderBy='-last_shown')[index].full_name
-print(filename.encode(output_encoding))
+sys.stdout.buffer.write(filename.encode(output_encoding) + b'\n')