 <span class="o">==</span> <span class="kc">None</span><span class="p">)</span> <span class="o">|</span> <span class="p">(</span><span class="n">KLCH</span> <span class="o">==</span> <span class="p">[</span><span class="mi">1</span><span class="p">,</span><span class="mi">1</span><span class="p">,</span><span class="mi">1</span><span class="p">]):</span>
            <span class="c1"># Calculate color difference and take account of KL:</span>
            <span class="n">DEi</span> <span class="o">=</span> <s