def serialized(self):
        to_ret = {}
        for group, requirements in self.items():
            to_ret[group] = [str(requirement) for requirement in requirements]
        return to_ret
def visitdir(self, dir):
        dir = normalizerootdir(dir, "visitdir")
        visit1 = self._m1.visitdir(dir)
        if visit1 == "all":
            return self._m2.visitdir(dir)
        # bool() because visit1=True + visit2='all' should not be 'all'
        return bool(visit1 and self._m2.visitdir(dir))