t</span> <span class="o">=</span> <span class="nb">min</span><span class="p">(</span><span class="n">multiprocessing</span><span class="o">.</span><span class="n">cpu_count</span><span class="p">(),</span> <span class="nb">len</span><span class="p">(</span><span class="n">classes</span><span class="p">))</span>
    <span class="n">pool</span> <span class="o">=</span> <span class="n">multiprocessing</span><span class="o">.</span><span class="n">pool</span><span class="o">.</span><span class="n">ThreadPool</s