_to_piece_byname</a></span><span class="op">(</span>piece <span class="op">=</span> <span class="st">"from"</span>, margin <span class="op">=</span> <span class="st">"Product"</span><span class="op">)</span></span>
<span><span class="co">#&gt;       Motors -&gt; MD Cars -&gt; MD LED lamps -&gt; Light</span></span>
<span><span class="co">#&gt; Coal             1          2                  3</span></span>
<span><span class="co">#&gt; Solar            4          5                  6</span></span>
<span><span 