title: raise JSONDecodeError("Expecting value", s, err.value) from None Python
body: <p>I sometimes have this problem. But it's always resolved. This time impossible to find a solution. There are many post for the same subject but no resolution in my case.
  I am trying to get data from my api. It sometimes works(with data without none value) and with the data containing None value, it doesn't work. I think the problem is about the none values. I have this error</p>
  <pre><code>Exception Type: JSONDecodeError
  Exception Value:    
  Expecting value: line 1 column 75 (char 74)
  </code></pre>
  <p>Any help is appreciated.</p>
  <pre><code>@api_view(['GET'])
  def edges_of_a_network(request, pk):
      try:
          roadnetwork = RoadNetwork.objects.get(pk=pk)
      except RoadNetwork.DoesNotExist:
          return Response(status=status.HTTP_404_NOT_FOUND)
  
      else:
          edges = Edge.objects.filter(network=roadnetwork)
          edges = str(list(edges.values(&quot;edge_id&quot;, &quot;name&quot;,
              &quot;length&quot;, &quot;speed&quot;, &quot;lanes&quot;))).replace(&quot;'&quot;,'&quot;')
          edges = json.loads(edges)
          edges = json.dumps(edges, indent=2)
  
      if request.method == 'GET':
          return HttpResponse(edges, content_type=&quot;application/json&quot;)
  </code></pre>
  <p>screenshot
  <a href="https://i.stack.imgur.com/OVIcY.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/OVIcY.png" alt="enter image description here" /></a></p>