<span class="o">-</span><span class="mi">1</span>
        <span class="k">elif</span> <span class="nb">len</span><span class="p">(</span><span class="n">vertices</span><span class="p">)</span> <span class="o">==</span> <span class="mi">1</span><span class="p">:</span>
            <span class="k">return</span> <span class="mi">0</span>
        <span class="k">else</span><span class="p">:</span>
            <span class="n">vertices</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</sp