title: How to I set the Content Type of a Google Cloud Function HTTP response
body: <p>How do I set the <code>Content-Type</code> of a response from a HTTP Google Cloud Function in Python? Right now I have something like:</p>
  
  <pre><code>def my_function(request):
      xml = ...
      return xml
  </code></pre>
  
  <p>This correctly returns my XML, but the <code>Content-Type</code> is wrong (it's <code>text/html</code> instead).</p>