DatabaseModifiedError, how to handle it correctly when searching?

The starter guide [1] mentioned that searching could result in DatabaseModifiedError, and I need to reopen the database should it happen. However, I couldn’t figure out which functions throw that error, I looked at Enquire.get_mset(), etc, and none of them says they throw this error. How should I correctly handle this?

[1] https://getting-started-with-xapian.readthedocs.io/en/latest/practical_example/searching/database_modified.html

Thanks,
Yuan