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We put a special focus on the conformance testing aspect in active automata learning, as well as on an intuitive and seamlessly integrated interface for learning automata characterizing real-world reactive systems. In this article, we present <jats:sc>AALpy<\/jats:sc>\u2019s core functionalities, illustrate its usage via examples, and evaluate its learning performance. Finally, we present selected case studies on learning models of various types of systems with <jats:sc>AALpy<\/jats:sc>.<\/jats:p>","DOI":"10.1007\/s11334-022-00449-3","type":"journal-article","created":{"date-parts":[[2022,3,28]],"date-time":"2022-03-28T22:03:00Z","timestamp":1648504980000},"page":"417-426","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":46,"title":["AALpy: an active automata learning library"],"prefix":"10.1007","volume":"18","author":[{"given":"Edi","family":"Mu\u0161kardin","sequence":"first","affiliation":[]},{"given":"Bernhard K.","family":"Aichernig","sequence":"additional","affiliation":[]},{"given":"Ingo","family":"Pill","sequence":"additional","affiliation":[]},{"given":"Andrea","family":"Pferscher","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4193-5609","authenticated-orcid":false,"given":"Martin","family":"Tappler","sequence":"additional","affiliation":[]}],"member":"297","published-online":{"date-parts":[[2022,3,26]]},"reference":[{"key":"449_CR1","doi-asserted-by":"crossref","unstructured":"Aarts F, Jonsson B, Uijen J (2010) Generating models of infinite-state communication protocols using regular inference with abstraction. 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