/span><span class="n">copy</span><span class="p">(</span><span class="n">value</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">value</span> <span class="o">-</span> <span class="n">other</span><span class="o">.</span><span class="n">value</span><span class="p">)</span>


  <span class="k">def</span> <span class="nf">__mul__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</spa