电子邮件未在Celery任务中翻译

我有一个芹菜任务异步发送电子邮件

from djcelery.common import respects_language

@task(ignore_result=True)
@respects_language
def async_send_activation_email(registration_profile):
    registration_profile.send_activation_email()

并发送激活电子邮件功能

from django.core import context_processors

def send_activation_email(self):

    variables = {
                    'some_variable':'something',
        }
    context = context_processors.i18n(None) # Allows to easily get all the language information into context. None is passed as the request does not matter for this context_processor.


    # Subject
    # Email subject *must not* contain newlines
    subject = render_to_string(
        'user_manager/activation/email_subject.txt',
        variables,
        context
        )
            ...

context包含正确的信息(在我的例子中是LANGUAGE ='fr',以及其他语言选项).这是正常的,因为它们由@respects_language装饰器正确设置.

但无论如何,render_to_string都使用了后备语言.

关于可能发生的事情的任何想法？