def __str__(self):
        """
        String representation
        """
        return "({0}{1})".format(
            operator2str(self.operator),
            "".join(str(subfilter) for subfilter in self.subfilters),
        )
def __str__ ( self ) : return "({0}{1})" . format ( operator2str ( self . operator ) , "" . join ( str ( subfilter ) for subfilter in self . subfilters ) , )
String representation