[Python] how to apply filters on a posgres JSONField in django rest framework?

I have a model similar to this:

# segment/models.py
from django.db import models
from django.contrib.postgres.fields import JSONField

class Segment(models.Model):
name = models.CharField(max_length=100)
# docs: https://docs.djangoproject.com/en/2.2/ref/contrib/postgres/fields/#jsonfield
data = JSONField('data', 'data')



in field data I store JSON data similar to this

{
"length": 123.45
"difficulty": {
"avg": "easy"
"max": "advanced"
}
}


I would like to be able to query data as following:

• api/segments/?data__difficulty__avg=easy

to filter all records where

• data.difficulty.avg="easy".

to do this, I set up the serializer:

# api/serializers.py
from rest_framework import serializers

class SegmentSerializer(serializers.ModelSerializer):
class Meta:
model = Segment
fields = ['id', 'name', 'data']


and the view looks like this:

# api/views.py
from django_filters.rest_framework import DjangoFilterBackend
from .serializers import SegmentSerializer
from segment.models import Segment

class SegmentViewSet(viewsets.ReadOnlyModelViewSet):
queryset = Segment.objects.all()
serializer_class = SegmentSerializer
filter_backends = [DjangoFilterBackend]
filterset_fields = ['id', 'name', 'data']


when I call

• api/segments

I get the following error

AssertionError at /api/segments/
AutoFilterSet resolved field 'data' with 'exact' lookup to an unrecognized field type JSONField. Try adding an override to 'Meta.filter_overrides'. See: https://django-filter.readthedocs.io/en/master/ref/filterset.html#customise-filter-generation-with-filter-overrides

Request Method: GET
Request URL: http://localhost:8000/api/segments/
Django Version: 2.2.7
Python Executable: /Users/udos/.virtualenvs/ts/bin/python
Python Version: 3.6.4
.
.
.


I tried adding data = serializers.JSONField() to the serializer:

# api/serializers.py
from rest_framework import serializers

class SegmentSerializer(serializers.ModelSerializer):
data = serializers.JSONField()
class Meta:
model = Segment
fields = ['id', 'name', 'data']


but the error persists. so I'm not applying it correctly :|

how is this done properly?

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