title: Prometheus python client error Address already in use
body: <p>I'm running a web app with address 127.0.0.1:5000 and am using the python client library for Prometheus. I use <code>start_http_server(8000)</code> from the example in their <a href="https://github.com/prometheus/client_python" rel="noreferrer">docs</a> to expose the metrics on that port. The application runs, but I get <code>[Errno 48] Address already in use</code> and the localhost:8000 doesn't connect to anything when I try hitting it.</p>
  
  <p>If I can't start two servers from one web app, then what port should I pass into <code>start_http_server()</code> in order to expose the metrics?</p>
  
  <p>There is nothing already running on either port before I start the app.</p>