code: def process_request(self, request):
          
          if not self.is_resource_protected(request):
              return
  
          if self.deny_access_condition(request):
              return self.deny_access(request)
docs: The actual middleware method, called on all incoming requests.
  
          This default implementation will ignore the middleware (return None) if the
          conditions specified in is_resource_protected aren't met. If they are, it then
          tests to see if the user should be denied access via the denied_access_condition
          method, and calls deny_access (which implements failure behaviour) if so.