def __len__(self):  # O(logN)
        """Drop all expired items and return the remaining length"""
        with self._lock:
            sequence, timestamps = self._mapping.get(self._INDEX, ([], {}))
            self._maintenance(sequence, timestamps)  # O(logN)
            self._mapping[self._INDEX] = sequence, timestamps
            return len(timestamps)  # Faster than iter(self._mapping) when it is on disk
Drop all expired items and return the remaining length
Solutions/CyberArkAudit/Data Connectors/.python_packages/lib/site-packages/msal/individual_cache.py