ss="nd">@preprocessing_fn</span>
<span class="k">def</span> <span class="nf">toy_cls</span><span class="p">(</span><span class="n">params</span><span class="p">:</span> <span class="n">Params</span><span class="p">,</span> <span class="n">mode</span><span class="p">:</span> <span class="nb">str</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="n">Tuple</span><span class="p">[</span><span class="nb">list</span><span class="p">,</span> <span class="nb">list</span><span class="p">]:</spa