<metal:block use-macro="here/widget_macro/macros/widget">
    <metal:block fill-slot="input">
        <input type="text" tal:attributes="
            value value;
            size here/width;
            maxlength python:test(here.size_max, here.size_max, None);
            name string:${prop_id}:utf8:ustring;
            id prop_id" />
    </metal:block>
</metal:block>
