pan class="n">x_parent</span><span class="o">=</span><span class="n">x_pos</span><span
            class="p">,</span> <span class="n">y_parent</span><span class="o">=</span><span class="n">y_pos</span><span
            class="p">)</span>
        <span class="k">if</span> <span class="n">node</span><span class="o">.</span><span class="n">right</span><span
            class="p">:</span>
            <span class="k">if</span> <span class="n">y_parent</span><span class="p">:</span>
                <span class="n