span class="sd">    Raises:</span>
<span class="sd">      ValueError: when argument is not a Coord object</span>
<span class="sd">    &quot;&quot;&quot;</span>

    <span class="k">if</span> <span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">other</span><span class="p">,</span><span class="n">Valued</span><span class="p">):</span>
      <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s">&#39;Error: provide 