<span class="o">==</span> <span class="n">gridy</span><span class="p">:</span>
            <span class="n">grid</span> <span class="o">=</span> <span class="n">gridx</span>
        <span class="k">else</span><span class="p">:</span>
            <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s1">&#39;GRID parameter contains two &#39;</span>
                             <span class="s1">&#39;different values: </span><span class="si">%s</span><span class="s1