Custom TV Type and [Cannot redeclare class modTemplateVarInputRenderText]

hi there
i use modx 2.4.2 and just try to follow this article step my step: https://rtfm.modx.com/revolution/2.x/making-sites-with-modx/customizing-content/template-variables/adding-a-custom-tv-type-modx-2.2
to create my own custom tv type.

But modx script crashes with error:

PHP Fatal error: Cannot redeclare class modTemplateVarInputRenderText in /var/www/vhosts/modx.local/www/core/model/modx/processors/element/tv/renders/mgr/input/text.class.php on line 0

i did not create pathing plugin, such as the article says:

The pathing plugin will not be required in MODX 2.3; the Namespace will handle all the pathing. This is why we told you earlier to make the Namespace.

so, what's wrong with it? How to create my own Custom TV Type with namespases for modx?

what's the path and the code of your custom TV Type, now?

Did you wrap your class like this, as shown in the tutorial (using the same class name as the enclosed class)?

if(!class_exists('modTemplateVarInputRenderText')) {
// ...

}