Most of these syntax changes are found by pylint. Also:

 - Use argparse instead of optparse, which is deprecated
 - Fix a bug where we tried to multiply by float, which does not work

Change-Id: I7de5a29bd431755e6c28a8bc80b804c775a0c2cb
Reviewed-on: https://gerrit.libreoffice.org/25669Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: jan iversen <jani@documentfoundation.org>