def clean_group(self):
        group = self.cleaned_data['group']
        if Team.objects.filter(
            group = group,
            project = self.instance.project,
        ).count() >= 0:
            raise forms.ValidationError(_("This group is already a team "
                "of this project"))
        return group
dataset/ETHPy150Open lukaszb/django-projector/projector/forms.py/TeamForm.clean_group/operator `>` -> `>=`