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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_servers_deque(servers, database):
 """ Returns deque of servers for given tuple of servers and database name. This deque have active server at the begining, if first server is not accessible at the moment the deque will be rotated, second server will be moved to the first position, thirt to the second position etc, and previously first server will be moved to the last position. This allows to remember last successful server between calls to connect function. """

    key = (servers, database)
    if key not in _servers_deques:
        _servers_deques[key] = deque(servers)
    return _servers_deques[key]