span class="n">_memoryUSS</span> <span class="o">=</span> <span class="nb">float</span><span class="p">()</span>
    <span class="n">_memoryRSS</span> <span class="o">=</span> <span class="nb">float</span><span class="p">()</span>
    <span class="n">_Database</span> <span class="o">=</span> <span class="p">[]</span>

    <span class="k">def</span> <span class="nf">_creatingItemSets</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="k