title: Python: How to Use Requests Library to Access Flask RestPlus API hosted on Google App Engine?
body: <p>I built a rest api using flask restplus and I tested it using the swagger documentation, and it seems to be fully functional and working just fine. I now want to test the API using the python requests library, but I'm getting the following error:</p>
  <pre><code>Invalid IAP credentials: empty token
  </code></pre>
  <p>I imagine this is because I did not authorize using the credentials. I do have access to the service account credentials json file, but just wondering how I pass this into requests?</p>
  <p>Code Example:</p>
  <pre><code>url = 'https://crosssellapi-project-id.appspot.com/auth/login'
  
  r = requests.get(url, headers={'accept': 'application/json'})
  </code></pre>
  <p>Thanks in advance.</p>