=</span> <span class="p">[</span><span class="n">values</span><span class="p">]</span>
        <span class="k">if</span> <span class="ow">not</span> <span class="n">res</span> <span class="ow">or</span> <span class="n">d</span><span class="p">[</span><span class="s1">&#39;step&#39;</span><span class="p">]</span> <span class="o">-</span> <span class="n">res</span><span class="p">[</span><span class="o">-</span><span class="mi">1</span><span class="p">][</span><span class="s1">&#39;step&#39;</span><span class