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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 get_versioned_delete_collector_class():
 """ Gets the class to use for deletion collection. :return: class """

    key = 'VERSIONED_DELETE_COLLECTOR'
    try:
        cls = _cache[key]
    except KeyError:
        collector_class_string = getattr(settings, key)
        cls = import_from_string(collector_class_string, key)
        _cache[key] = cls
    return cls