><span class="co">#&gt;                          Motors -&gt; MD Cars -&gt; MD LED lamps -&gt; Light</span></span>
<span><span class="co">#&gt; Electricity [from Coal]             1          2                  3</span></span>
<span><span class="co">#&gt; Electricity [from Solar]            4          5                  6</span></span>
<span><span class="va">res</span> <span class="op">&lt;-</span> <span class="fu"><a href="../reference/rename_to_piece_byname.html">rename_to_piece_byname</a></span><span clas