title: Python str formatting
body: <p><strong>Python 3.8.10</strong></p>
  <pre><code>result = &quot;&lt;svg id='{id}' class='{class}' height='{height}{unit}' width='{width}{unit}'&gt;&quot;.format(id=image_id, class=html_class, height=str(height), unit=unit_of_measure)
  </code></pre>
  <p>I get this error message:</p>
  <pre><code> File &quot;/home/michael/PycharmProjects/images_outer/images_project/images/templatetags/images.py&quot;, line 131
      result = &quot;&lt;svg id='{id}' class='{class}' height='{height}{unit}' width='{width}{unit}'&gt;&quot;.format(id=image_id, class=html_class, height=str(height), unit=str(unit_of_measure))
                                                                                                                   ^
  SyntaxError: invalid syntax
  python-BaseException
  
  Process finished with exit code 130 (interrupted by signal 2: SIGINT)
  </code></pre>
  <p>Could you help me?</p>