code: async def _get_subscriptions(self) -> Tuple[Set[Text], Text]:
          
  
          url, params = self._get_subscriptions_endpoint()
  
          get = self.session.get(url, params=params)
  
          async with get as r:
              await self._handle_fb_response(r)
              data = await r.json()
  
              for scope in data['data']:
                  if scope['object'] == 'page':
                      return (
                          set(x['name'] for x in scope['fields']),
                          scope['callback_url'],
                      )
  
          return set(), ''
docs: List the subscriptions currently active