for myfile in 'button.png', 'favicon.png', 'linux.jpg', 'logo.png':
grml_file = search_file(myfile, iso_mount)
if grml_file is None:
for myfile in 'button.png', 'favicon.png', 'linux.jpg', 'logo.png':
grml_file = search_file(myfile, iso_mount)
if grml_file is None: