What should be included in the custom `toString()` method of a class?
A custom `toString()` method should always return a string containing the object's `hashCode()` to help with object identification.
Satisfactory! While including the `hashCode()` can be useful in some cases, the `toString()` method should primarily return the object's relevant state, not just the `hashCode()`.
Can you explain the role of `hashCode()` and when it might be useful to include it in the `toString()` method?