def METHOD_NAME(self):
    v1 = OptVariable("a", 2, 0, 3, description="test")
    assert v1.name == "a"
    assert v1.value == 2
    assert v1.lower_bound == 0
    assert v1.upper_bound == 3
    assert v1.description == "test"
    v2 = OptVariable("b", 0, -1, 1)
    assert v2.name == "b"
    assert v2.value == 0
    assert v2.lower_bound == -1
    assert v2.upper_bound == 1
    assert v2.description is None
    with pytest.raises(OptVariablesError):
        v3 = OptVariable("a", 2, 2.5, 3)