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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 present(name):
    '''
    Ensure the RabbitMQ VHost exists.

    name
        VHost name

    user
        Initial user permission to set on the VHost, if present

        .. deprecated:: 2015.8.0
    owner
        Initial owner permission to set on the VHost, if present

        .. deprecated:: 2015.8.0
    conf
        Initial conf string to apply to the VHost and user. Defaults to .*

        .. deprecated:: 2015.8.0
    write
        Initial write permissions to apply to the VHost and user.
        Defaults to .*

        .. deprecated:: 2015.8.0
    read
        Initial read permissions to apply to the VHost and user.
        Defaults to .*

        .. deprecated:: 2015.8.0
    runas
        Name of the user to run the command

        .. deprecated:: 2015.8.0
    '''
    ret = {'name': name, 'result': True, 'comment': '', 'changes': {}}

    vhost_exists = __salt__['rabbitmq.vhost_exists'](name)

    if vhost_exists:
        ret['comment'] = 'Virtual Host \'{0}\' already exists.'.format(name)
        return ret

    if not __opts__['test']:
        result = __salt__['rabbitmq.add_vhost'](name)
        if 'Error' in result:
            ret['result'] = False
            ret['comment'] = result['Error']
            return ret
        elif 'Added' in result:
            ret['comment'] = result['Added']

    # If we've reached this far before returning, we have changes.
    ret['changes'] = {'old': '', 'new': name}

    if __opts__['test']:
        ret['result'] = None
        ret['comment'] = 'Virtual Host \'{0}\' will be created.'.format(name)

    return ret