The Twital instruction for Twig import tag is t:sandbox node or the t:sandbox attribute.

The sandbox tag can be used to enable the sandboxing mode for an included template, when sandboxing is not enabled globally for the Twig environment:

    {% include 'user.html' %}

<div t:sandbox="">
    {% include 'user.html' %}


For more information about the sandbox tag, please refer to Twig official documentation.