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This PR recreates #33 step by step because it branched off 855b713 from September 18th 2023, rather than from 6aa8daf from January 26th 2024, meaning that it was many essential changes and error corrections. Also, commits aiming at eliminating warnings have been filtered out because they belong to a different task which has partially been accomplished by @BeckerHanne during the afore-mentioned period.