title: Gmail App - Quickstart, Error: redirect_uri_mismatch
body: <p>I'm following the Google Developer "Quickstart: Run a Gmail App in Python"
  <a href="https://developers.google.com/gmail/api/quickstart/quickstart-python" rel="nofollow">https://developers.google.com/gmail/api/quickstart/quickstart-python</a></p>
  
  <p>All is ok up to step 3 "Run the sample", where the instructions say to "Run the sample using python quickstart.py."</p>
  
  <p>When I do this, the expected result is my browser would load and start the authorization. Instead, I get the Error 400 page on Google. </p>
  
  <pre><code>Error: redirect_uri_mismatch
  
  The redirect URI in the request: http://localhost:8080/ did not match a registered redirect URI
  </code></pre>
  
  <p>Problem is, "localhost..." is not in redirect URIs, I've checked many other questions similar to this, usually the answers suggest confirming the URL's are EXACTLY the same. I've done that, https/http, additional backslashes, all is identical. Google still says I'm sending localhost:8080.</p>