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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 _check_and_uninstall_ruby(ret, ruby, user=None):
    '''
    Verify that ruby is uninstalled
    '''
    ret = _ruby_installed(ret, ruby, user=user)
    if ret['result']:
        if ret['default']:
            __salt__['rbenv.default']('system', runas=user)

        if __salt__['rbenv.uninstall_ruby'](ruby, runas=user):
            ret['result'] = True
            ret['changes'][ruby] = 'Uninstalled'
            ret['comment'] = 'Successfully removed ruby'
            return ret
        else:
            ret['result'] = False
            ret['comment'] = 'Failed to uninstall ruby'
            return ret
    else:
        ret['result'] = True
        ret['comment'] = 'Ruby {0} is already absent'.format(ruby)

    return ret