django - GeoDjango: Distance Object is not serializable -

i learning geo-django. can find out distance of places point. when use .values method annotated distance field, getting

typeerror: object of type 'distance' not json serializable

here code snippets

#models.py import uuid django.contrib.gis.db import models django.contrib.gis.db.models.functions import distance django.contrib.gis.geos import point class placemanager(models.geomanager):     def get_queryset(self):         qs = super(placemanager, self).get_queryset()         qs = qs.annotate(         latitude=models.expressionwrapper(models.func('position', function='st_x'), output_field=models.floatfield()),         longitude=models.expressionwrapper(models.func('position', function='st_y'), output_field=models.floatfield()),     )     return qs.distinct()      def nearby_places(self, lat, lng):         p = point(lat, lng, srid=4326)         qs = self.get_queryset()         qs = qs.annotate(             distance=distance('position', p)         )         return qs.order_by('distance').distinct()   class place(models.model):     id = models.uuidfield(default=uuid.uuid4, editable=false, primary_key=true, db_index=true)     position = models.pointfield()     address = models.textfield(default=none, null=true, blank=true)     objects = placemanager()      def __str__(self):         return '{},{}'.format(self.position.x, self.position.y) 

now code snippets have this

from rest_framework.views import apiview rest_framework import status rest_framework.response import response  class nearbyplaces(apiview):     def get(self, request):         p = place.objects.nearby_places(30.45, -90.43)         p = p.values('distance', 'address', 'latitude', 'longitude')         return response(p, status=status.http_200_ok) 

the value of p here this

<geoqueryset [{'distance': distance(m=7596021.71574835), 'address': 'new york city, new york','latitude': 13.4586, 'longitude': 45.6789}]> 

so needed here 'distance': 7596021.71574835 instead of 'distance': distance(m=7596021.71574835)

any on this? in advance.

just found way it. had make renderer class in rest framework , handled distance objects in there. code snippets this.

encoders.py

from rest_framework.utils.encoders import jsonencoder django.contrib.gis.measure import distance   class customjsonencoderwithdistance(jsonencoder):     def default(self, obj):         if isinstance(obj, distance):             print(obj)             return obj.m         return super(customjsonencoderwithdistance, self).default(obj) 

renders.py

from rest_framework.renderers import jsonrenderer .encoders import customjsonencoderwithdistance   class customjsonrenderer(jsonrenderer):      encoder_class = customjsonencoderwithdistance 

settings.py

... rest_framework = {     'default_renderer_classes': (         'app.renderers.customjsonrenderer',     ) }