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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 attached(name, force=False):
    '''
    Ensure zone is attached

    name : string
        name of the zone
    force : boolean
        force attach the zone

    '''
    ret = {'name': name,
           'changes': {},
           'result': None,
           'comment': ''}

    zones = __salt__['zoneadm.list'](installed=True, configured=True)
    if name in zones:
        if zones[name]['state'] == 'configured':
            if __opts__['test']:
                res_attach = {'status': True}
            else:
                res_attach = __salt__['zoneadm.attach'](name, force)
            ret['result'] = res_attach['status']
            if ret['result']:
                ret['changes'][name] = 'attached'
                ret['comment'] = 'The zone {0} was attached.'.format(name)
            else:
                ret['comment'] = []
                ret['comment'].append('Failed to attach zone {0}!'.format(name))
                if 'message' in res_attach:
                    ret['comment'].append(res_attach['message'])
                ret['comment'] = "\n".join(ret['comment'])
        else:
            ret['result'] = True
            ret['comment'] = 'zone {0} already attached.'.format(name)
    else:
        ret['result'] = False
        ret['comment'] = 'zone {0} is not configured!'.format(name)

    return ret