text: Title: "Connection is already acquired" error
  Body: Hi. I have a daemon with several asyncio tasks, each of which executes some requests. All of the tasks share the same connection.
  
  After some time one of them begins to produce this error.
  
  Failed code is simple :)
  
  In main.py I have
  `self.engine = Database(config.Config.SQLALCHEMY_DATABASE_URI)
   await self.engine.connect()
  `
  
  And in broken task
  `await wait_for(self.engine.execute(query=statement), 10)
  `
  What could be wrong?