async - sync - async calls in one python event loop

Let's say I have a class which uses asyncio loop internally and doesn't have async interface:

class Fetcher:
    _loop = None
    def get_result(...):
        """
        After 3 nested sync calls async tasks are finally called with *run_until_complete*
        """
        ...

I use all advantages of asyncio internally and don't have to care about it in the outer code.

But then I want to call 3 Fetcher instances in one event loop. If I had async def interface there would be no problem: asyncio.gather could help me. Is there really no other way to do it without supporting both interfaces? Come on! It makes you change all your project because of one asyncio usage. Tell me this is not true.