def make_mo(self, po_filename, mo_filename):
        """Create a machine object (.mo) from a portable object (.po) file."""
        try:
            call(['msgfmt', po_filename, '-o', mo_filename])
        except OSError as e:
            # ignore failures since i18n support is optional:
            logging.warning(e)
Create a machine object (.mo) from a portable object (.po) file.