List custom taxonomy terms in a specific order (not alphabetical)

We need to do that slightly differently, based on this example: https://gohugo.io/templates/taxonomy-templates/#site-getpage-for-taxonomies

{{ $taxo := "difficulty" }}
<ul>
  {{ with ($.Site.GetPage (printf "/%s" $taxo)) }}
    {{ range .Pages.ByWeight }}
      <li><a href="{{ .Permalink }}">{{ .Title}}</a>
        <ul>
          {{ range .Pages }}
          <!-- this also lists the content pages associated with the term; 
               remove if not needed. -->
          <li>{{ .Title }}</li>
          {{ end }}
        </ul>
      </li>
    {{ end }}
  {{ end }}
</ul>