def __missing__(self, key):
        if self.default_factory is None:
            raise KeyError(key)
        else:
            ret = self[key] = self.default_factory(name=key)
            return ret
def test_ccode_constants_mathh():
    assert ccode(exp(1)) == "M_E"
    assert ccode(pi) == "M_PI"
    assert ccode(oo) == "HUGE_VAL"
    assert ccode(-oo) == "-HUGE_VAL"