def __repr__(self):
        return "<NamedRequirements({}{})>".format(
            self.name,
            ", filename='{}'".format(self.filename.name) if self.filename
            else "")
def test_ccode_exceptions():
    assert ccode(ceiling(x)) == "ceil(x)"
    assert ccode(Abs(x)) == "fabs(x)"
    assert ccode(gamma(x)) == "tgamma(x)"