How do you access query params in a Django Rest Framework 3.0 serializer?

In Django Rest Framework 2.x you could access, for example, the "fields" query parameter in a serializer like this: ``` fields = self.context['request'].QUERY_PARAMS.get('fields') ``` That no longer works in DRF 3.0, but I can't find the change documented in the API except in general terms. It looks like it might be something like `self.context.get('request')?????` but I can't figure it out. How would you do it in DRF 3.0? I'm talking about accessing the query.params in the serializer rather than in the view. thanks John