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class Person {
    private Car car;

    public Car getCar() {
        return car;
    }
}

class Car {
    private Insurance insurance;

    public Insurance getInsurance() {
        return insurance;
    }
}

class Insurance {
    private String name;

    public String getName() {
        return name;
    }
}

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public String getCarInsuranceName(Person person) {
    return person.getCar().getInsurance().getName();
}

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public String getCarInsuranceNameV1(Person person) {
    if (person != null) {
        Car car = person.getCar();
        if (car != null) {
            Insurance insurance = car.getInsurance();
            if (insurance != null) {
                return insurance.getName();
            }
        }
    }
    return "Unknow";
}

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public String getCarInsuranceNameV2(Person person) {
    if (person == null) {
        return "Unknow";
    }
    Car car = person.getCar();
    if (car == null) {
        return "Unknow";
    }
    Insurance insurance = car.getInsurance();
    if (insurance == null) {
        return "Unknow";
    }
    return insurance.getName();
}