python - django get sum of column based on where clause -


i have read documentation related django aggregation still have trouble figuring out how can sum of points per user.

here tried: 

modelname.objects.filter(username=ruser.username).aggregate(sum('points'))

i following error:

request method: request url:    http://localhost:8001/mypage/ django version: 1.4.8 exception type: nameerror exception value:     global name 'sum' not defined

you need import sum first:

from django.db.models import sum

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