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Peter: A Use Case is a format for describing a functional requirement (at least that's the intention from our side when using it here). The use case can be extgremely extremely simple (pre- and post conditions and the step "do it") where it is up to the implementation (the use case realization) to dicide "how to do it" - or the use case can outline in rough steps how it shall be done - in which case that sequence of rough steps is part of the requirement. Hence, we should not make the use case description too detailed.
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