title: Fail: AttributeError: module 'collections' has no attribute 'Container'
body: <p>I try to start <code>python-pptx</code>, but I have Error:</p>
  <pre><code>AttributeError: module 'collections' has no attribute 'Container'
  in File &quot;...\lib\site-packages\pptx_init_.py&quot;, line 14 
  </code></pre>
  <p>Use Python 3.10, python-pptx (0.6.21), lxmx (4.6.3).</p>
  <p>Please, help me.</p>