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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 is_auth(nodes):
    '''
    Check if nodes are already authorized

    nodes
        a list of nodes to be checked for authorization to the cluster

    CLI Example:

    .. code-block:: bash

        salt '*' pcs.is_auth nodes='[node1.example.org node2.example.org]'
    '''
    cmd = ['pcs', 'cluster', 'auth']
    cmd += nodes

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