Can not parse Chebi ontology files?

[wanglu2014]

Chebi is one of the most used sources in life science.
https://ftp.ebi.ac.uk/pub/databases/chebi/ontology/nightly/
All owl and obo files can not be correctly opened by owlready2.
code:
ontobo = get_ontology("D:/installed/PyCharm Community Edition 2022.2.3/Ontpy/chebi_lite_night.owl").load()
res=ontobo.one of the class

then the res is None

For a double check, I tried a software Protege to open them, then get an empty field.