def _stringify(self, transform: StringifyTransform) -> str:
    res = ', '.join((transform(a) for a in self.args))
    if self.packExpansion:
        res += '...'
    return (('<' + res) + '>')
def _stringify(self, transform: StringifyTransform) -> str:
    res = ', '.join((transform(a) for a in self.args))
    if self.packExpansion:
        res += '...'
    return (('<' + res) + '>')