def _stringify(self, transform: StringifyTransform) -> str:
    exprs = [transform(e) for e in self.exprs]
    return ('(%s)' % ', '.join(exprs))
def _stringify(self, transform: StringifyTransform) -> str:
    exprs = [transform(e) for e in self.exprs]
    return ('(%s)' % ', '.join(exprs))