title: Python MySQLClient installation fails with "metadata-generation-failed"
body: <p>Well, I have &quot;googled it&quot; without finding an answer.  Routine updates of a Python-based site, based on its <code>requirements.txt</code>,  now fail with <strong>metadata-generation-failed</strong> when attempting to update &quot;mysqlclient.&quot;  The question is why.</p>