/span><span class="p">)</span>
        <span class="n">labr</span> <span class="o">=</span> <span class="n">xyz_to_lab</span><span class="p">(</span><span class="n">xyzr</span><span class="p">,</span> <span class="n">xyzw</span> <span class="o">=</span> <span class="n">xyzwr</span><span class="p">)</span>
    <span class="k">else</span><span class="p">:</span>
        <span class="n">labt</span> <span class="o">=</span> <span class="n">xyzt</span>
        <span class="n">labr</span> <span class="o">=</span>