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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 running(concurrent=False):
    '''
    Return a list of strings that contain state return data if a state function
    is already running. This function is used to prevent multiple state calls
    from being run at the same time.

    CLI Example:

    .. code-block:: bash

        salt '*' state.running
    '''
    ret = []
    if concurrent:
        return ret
    active = __salt__['saltutil.is_running']('state.*')
    for data in active:
        err = (
            'The function "{0}" is running as PID {1} and was started at '
            '{2} with jid {3}'
        ).format(
            data['fun'],
            data['pid'],
            salt.utils.jid.jid_to_time(data['jid']),
            data['jid'],
        )
        ret.append(err)
    return ret