This leads to an error message when opening the ontology in Protege:
Illegal redeclarations of entities: reuse of entity http://purl.org/dc/terms/source in punning not allowed [Declaration(ObjectProperty(<http://purl.org/dc/terms/source>)), Declaration(AnnotationProperty(<http://purl.org/dc/terms/source>))]
And also throws a TypeError when trying to load using owlready2:
TypeError: Property 'http://purl.org/dc/terms/source' is both an ObjectProperty and an AnnotationProperty!
I can't say I completely understand the issue, but I think it is a difference between what is allowed in OWL Full and in OWL DL (the latter does not allow reuse between ObjectProperty and AnnotationProperty entities).
sepio.owl includes http://purl.org/dc/terms/source as both an ObjectProperty and an AnnotationProperty
This leads to an error message when opening the ontology in Protege:
And also throws a TypeError when trying to load using owlready2: