span> <span class="n">item</span> <span class="ow">in</span> <span class="n">transaction</span><span class="p">:</span>
                        <span class="k">if</span> <span class="n">item</span> <span class="ow">in</span> <span class="n">tidSets</span><span class="p">:</span>
                            <span class="n">tidSets</span><span class="p">[</span><span class="n">item</span><span class="p">]</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">transNum<