title: async - sync - async calls in one python event loop
body: <p>Let's say I have a class which uses asyncio loop internally and doesn't have async interface: </p>
  
  <pre><code>class Fetcher:
      _loop = None
      def get_result(...):
          """
          After 3 nested sync calls async tasks are finally called with *run_until_complete*
          """
          ...
  </code></pre>
  
  <p>I use all advantages of asyncio internally and don't have to care about it in the outer code.</p>
  
  <p>But then I want to call 3 <code>Fetcher</code> instances in one event loop. If I had <code>async def</code> interface there would be no problem: <code>asyncio.gather</code> could help me. Is there really no other way to do it without supporting <a href="https://stackoverflow.com/a/30163654/1401639">both interfaces</a>? Come on! It makes you change all your project because of one asyncio usage. Tell me this is not true.</p>