@Override
 public Response execute(Request request) throws IOException {
   List<Header> headers = request.getHeaders();
   List<retrofit.client.Header> modified = new ArrayList<Header>();
   for (int i = 0; i < headers.size(); i++) {
     retrofit.client.Header header = headers.get(i);
     if (!header.getName().equals("Content-Length")) {
       modified.add(header);
     }
   }
   return super.execute(
       new Request(request.getMethod(), request.getUrl(), modified, request.getBody()));
 }