code: def httpretty_callback(request, uri, headers):
      
      method = request.method
      response_headers = CaseInsensitiveDict()
      response_headers.update(headers)
      request_headers = CaseInsensitiveDict()
      request_headers.update(request.headers)
      request.headers = request_headers
      return StackInABox.call_into(method,
                                   request,
                                   uri,
                                   response_headers)
docs: httpretty request handler.
  
      converts a call intercepted by httpretty to
      the stack-in-a-box infrastructure
  
      :param request: request object
      :param uri: the uri of the request
      :param headers: headers for the response
  
      :returns: tuple - (int, dict, string) containing:
                        int - the http response status code
                        dict - the headers for the http response
                        string - http string response