foundry/Data/systems/pf2e/templates/sidebar/party-document-partial.hbs

<ol class="party-list">
{{#each parties}}
    <li class="party flexcol {{#unless (lookup @root.extraFolders this.id)}}collapsed{{/unless}}" data-document-id="{{this.id}}">
        <header class="directory-item party-header flexrow" data-document-id="{{this.id}}">
            <i class="fas fa-fw fa-users" data-action="open-sheet"></i>
            <h3 class="noborder">{{this.name}}</h3>
            <div class="controls">
                <a class="create-button" data-action="create-member">
                    <i class="fas fa-user-plus"></i>
                </a>
            </div>
        </header>

        <ol class="subdirectory">
            {{#each this.members}}
            {{> (lookup @root "documentPartial")}}
            {{/each~}}
        </ol>
    </li>
{{/each}}
</ol>