>=</span> <span class="n">node</span>
            <span class="bp">self</span><span class="o">.</span><span class="n">last</span><span class="o">.</span><span
            class="n">suc</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span
            class="n">first</span>
            <span class="bp">self</span><span class="o">.</span><span class="n">first</span><span
            class="o">.</span><span class="n">pred</span> <span class="o">=</span> <span class="n">node<