 class="o">.</span><span class="n">imshow</span><span class="p">(</span><span class="n">cvg_background</span><span class="p">,</span> <span class="n">origin</span> <span class="o">=</span> <span class="s1">&#39;upper&#39;</span><span class="p">,</span> <span class="n">extent</span> <span class="o">=</span> <span class="n">axis_</span><span class="p">)</span>
            <span class="n">_CVG_BG</span> <span class="o">=</span> <span class="n">cvg_background</span>

    <span class="k">return</span> <span clas