def get_value(self, key, args, kwargs):
        """
        Replaces colon in kwarg keys with an underscore before getting value.

        Missing identifiers are replaced with the default value.
        """
        kwargs = {k.replace(":", "_"): v for k, v in kwargs.items()}
        try:
            return pangocffi.markup_escape_text(
                string.Formatter.get_value(self, key, args, kwargs)
            )
        except (IndexError, KeyError):
            return self._default

        Replaces colon in kwarg keys with an underscore before getting value.

        Missing identifiers are replaced with the default value.
        
libqtile/widget/mpris2widget.py