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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 cluster_setup(nodes, pcsclustername='pcscluster', extra_args=None):
    '''
    Setup pacemaker cluster via pcs command

    nodes
        a list of nodes which should be set up
    pcsclustername
        Name of the Pacemaker cluster (default: pcscluster)
    extra_args
        list of extra option for the \'pcs cluster setup\' command

    CLI Example:

    .. code-block:: bash

        salt '*' pcs.cluster_setup nodes='[ node1.example.org node2.example.org ]' pcsclustername=pcscluster
    '''
    cmd = ['pcs', 'cluster', 'setup']

    cmd += ['--name', pcsclustername]

    cmd += nodes
    if isinstance(extra_args, (list, tuple)):
        cmd += extra_args

    return __salt__['cmd.run_all'](cmd, output_loglevel='trace', python_shell=False)