> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_diffSets</span><span class="p">[</span><span class="n">item1</span><span class="p">][</span><span class="mi">0</span><span class="p">]</span> <span class="o">-</span> <span class="nb">len</span><span class="p">(</span><span class="n">unionDiffSet</span><span class="p">)</span>
                    <span class="k">if</span> <span class="n">unionSup</span> <span class="o">&gt;=</span> <span class="bp">self</span><sp