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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 property_present(name, property, value):
    '''
    Ensure property has a certain value

    name : string
        name of the zone
    property : string
        name of property
    value : string
        value of property

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

    ## sanitize input
    value = _parse_value(value)

    zones = __salt__['zoneadm.list'](installed=True, configured=True)
    if name in zones:
        ## zone exists
        zonecfg = __salt__['zonecfg.info'](name, show_all=True)
        if property not in zonecfg or zonecfg[property] != _parse_value(value):
            if __opts__['test']:
                ret['result'] = True
            else:
                # update property
                zonecfg_res = __salt__['zonecfg.set_property'](name, property, value)
                ret['result'] = zonecfg_res['status']
                if 'messages' in zonecfg_res:
                    ret['comment'] = zonecfg_res['message']
            if ret['result']:
                ret['changes'][property] = _parse_value(value)
                if ret['comment'] == '':
                    ret['comment'] = 'The property {0} is was updated to {1}.'.format(property, value)
            elif ret['comment'] == '':
                if ret['comment'] == '':
                    ret['comment'] = 'The property {0} is was not updated to {1}!'.format(property, value)
        else:
            ret['result'] = True
            ret['comment'] = 'The property {0} is already set to {1}.'.format(property, value)
    else:
        ## zone does not exist
        ret['result'] = False
        ret['comment'] = 'The zone {0} is not in the configured, installed, or booted state.'.format(name)

    return ret