Adding last modified date to articles

Hi,
I want to override custom/view/partials/meta.html.twig file so that I can add the last modified date as well as the published date.
Do you know how I go about this in twig? What is the name of the modified variable in Twig?

<span class="date">Last updated: {{ post.date(gantry.config.get('content.' ~ scope ~ '.meta-date.format', 'j F Y')) }}</span>

Thanks

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