>::</span><span class="w"> </span><span class="n">fill_level</span>

<span class="w">        </span><span class="n">N</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">size</span><span class="p">(</span><span class="n">A</span><span class="p">,</span><span class="w"> </span><span class="mi">1</span><span class="p">)</span>

<span class="w">        </span><span class="n">L</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mf