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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def process_records(records):
 """Converts queue entries into object changes. :param records: an iterable containing `LiveSyncQueueEntry` objects :return: a dict mapping object references to `SimpleChange` bitsets """

    changes = defaultdict(int)
    cascaded_update_records = set()
    cascaded_delete_records = set()

    for record in records:
        if record.change != ChangeType.deleted and record.object is None:
            # Skip entries which are not deletions but have no corresponding objects.
            # Probably they are updates for objects that got deleted afterwards.
            continue
        if record.change == ChangeType.created:
            assert record.type != EntryType.category
            changes[record.object] |= SimpleChange.created
        elif record.change == ChangeType.deleted:
            assert record.type != EntryType.category
            cascaded_delete_records.add(record)
        elif record.change in {ChangeType.moved, ChangeType.protection_changed}:
            cascaded_update_records.add(record)
        elif record.change == ChangeType.data_changed:
            assert record.type != EntryType.category
            changes[record.object] |= SimpleChange.updated

    for obj in _process_cascaded_category_contents(cascaded_update_records):
        changes[obj] |= SimpleChange.updated

    for obj in _process_cascaded_event_contents(cascaded_delete_records):
        changes[obj] |= SimpleChange.deleted

    return changes