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_exceptions():
    assert ccode(ceiling(x)) == "ceil(x)"
    assert ccode(Abs(x)) == "fabs(x)"
    assert ccode(gamma(x)) == "tgamma(x)"