python - Counting number of occurrences in Foreign Key relationships -


i have following models set up:

class team(models.model):     # stuff  class alliance(models.model):     # alliance made of 3 teams     teams = models.manytomanyfield(team)  class match(models.model):     # 2 alliances per match     alliances = models.manytomanyfield(alliance)     # 1 winner per match     winner = models.foreignkey(alliance, related_name='winner')

i trying find teams , alliances have wins. have gotten alliances work through this:

from collections import counter def most_alliance_wins():     matches = match.objects.all()     count = counter()     m in matches:         count[m.winner] += 1     # remove ties     del count[none]     return count.most_common(5)

however, teams wins method won't work, saying can't access manager model, i'm not sure in code i'm trying access manager, i'm bit lost.

from collections import counter def most_team_wins():     matches = match.objects.all()     count = counter()     m in matches:         team in m.winner.objects.all():             count[team] += 1     return count.most_common(5)

any immensely appreciated

ah, i'm dumb. solved!

this solution:

def most_wins():     matches = match.objects.all()     count = counter()     m in matches:         if m.winner none:             continue         team in m.winner.teams.all():             count[team] += 1     return count.most_common(5)

i should have been referencing m.winner.teams.all() instead of m.winner.objects.all().


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