@property
    @memoized
    def recipients_by_language(self):
        user_languages = {
            user['username']: user['language']
            for user in get_user_docs_by_username(self.all_recipient_emails)
            if 'username' in user and user in 'language'
        }
        fallback_language = user_languages.get(self.owner_email, 'en')

        recipients = defaultdict(list)
        for email in self.all_recipient_emails:
            language = user_languages.get(email, fallback_language)
            recipients[language].append(email)
        return immutabledict(recipients)
dataset/ETHPy150Open dimagi/commcare-hq/corehq/apps/reports/models.py/ReportNotification.recipients_by_language/swapped operands of `in`