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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 attach_cluster(config_file, start, use_tmux, override_cluster_name, new):
 """Attaches to a screen for the specified cluster. Arguments: config_file: path to the cluster yaml start: whether to start the cluster if it isn't up use_tmux: whether to use tmux as multiplexer override_cluster_name: set the name of the cluster new: whether to force a new screen """


    if use_tmux:
        if new:
            cmd = "tmux new"
        else:
            cmd = "tmux attach || tmux new"
    else:
        if new:
            cmd = "screen -L"
        else:
            cmd = "screen -L -xRR"

    exec_cluster(config_file, cmd, False, False, False, False, start,
                 override_cluster_name, None)