"s1">&#39;to&#39;</span> <span class="ow">in</span> <span class="n">number</span><span class="o">.</span><span class="n">lower</span><span class="p">()</span> <span class="ow">and</span> <span class="s1">&#39;by&#39;</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">number</span><span class="o">.</span><span class="n">lower</span><span class="p">():</span>
            <span class="n">number</span> <span class="o">=</span> <span class="s1">&#39;</span><span class="si">{:0&gt;3}</s