PyFCM: Subscribe a registration_id to multiple topics

PyFCM does support subscribe multiple registration_ids to a single topic. Which is:

push_service.subscribe_registration_ids_to_topic(registration_ids, topic)

But what if I need to subscribing a single registration to multiple topics.

As far as I read PyFCM's documentation, I can't find anything can satisfy my need.

I am currently using a for-loop to send single request per iteration but it doesn't seem like a good idea.

Do you know any better way than this? Thank in advance.