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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_event_id(object_type: str) -> str: """Return an event key for the event on the object type. This must be a unique event id for the object. Args: object_type (str):
 Type of object Returns: str, event id """

    key = _keys.event_counter(object_type)
    DB.watch(key, pipeline=True)
    count = DB.get_value(key)
    DB.increment(key)
    DB.execute()
    if count is None:
        count = 0
    return '{}_event_{:08d}'.format(object_type, int(count))