def parse(self, format_string):
        """
        Replaces first colon in format string with an underscore.

        This will cause issues if any identifier is provided that does not
        contain a colon. This should not happen according to the MPRIS2
        specification!
        """
        format_string = MPRIS_REGEX.sub(r"{\2_\3\4}", format_string)
        return string.Formatter.parse(self, format_string)

        Replaces first colon in format string with an underscore.

        This will cause issues if any identifier is provided that does not
        contain a colon. This should not happen according to the MPRIS2
        specification!
        
libqtile/widget/mpris2widget.py