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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 unlock():
    '''
    Unlocks the candidate configuration.

    CLI Example:

    .. code-block:: bash

        salt 'device_name' junos.unlock
    '''
    conn = __proxy__['junos.conn']()
    ret = {}
    ret['out'] = True
    try:
        conn.cu.unlock()
        ret['message'] = "Successfully unlocked the configuration."
    except jnpr.junos.exception.UnlockError as exception:
        ret['message'] = \
            'Could not unlock configuration due to : "{0}"'.format(exception)
        ret['out'] = False

    return ret