def create_mails(self, queryset):
        if hasattr(queryset, 'iterator') and callable(queryset.iterator):
            for receiver in queryset.iterator():
                self.create_mail(receiver)
        else:
            for receiver in queryset:
                self.create_mail(receiver)
Create mails for every NewsletterReceiverMixin in queryset.
dataset/ETHPy150Open allink/pennyblack/pennyblack/models/job.py/Job.create_mails