Reading annotations from MGH/MF Waveform Database (mghdb) results in the following error:

annotation = wfdb.rdann(record_path, extension='ari')

KeyError: 'Passing list-likes to .loc or [] with any missing labels is no longer supported, see https://pandas.pydata.org/pandas-docs/stable/user_guide/indexing.html#deprecate-loc-reindex-listlike'