ist of collections to search in</span>

<span class="sd">        :type collections: list</span>
<span class="sd">        &quot;&quot;&quot;</span>

        <span class="k">if</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">threads</span> <span class="o">&gt;</span> <span class="mi">1</span><span class="p">):</span>
            <span class="k">with</span> <span class="n">Parallel</span><span class="p">(</span><span class="n">n_jobs</span><span class="o">=</s