ass="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">_start_time</span><span class="p">:</span> <span class="n">Optional</span><span class="p">[</span><span class="n">Time</span><span class="p">]</span> <span class="o">=</span> <span class="kc">None</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">_end_time</span><span class="p">:</span> <span class="n">Optional</span><span class="p">[</span><span class="n">Time</span><span class="p"