singleton should be scoped to event loop

yente/provider/base.py

@@ -1,20 +1,21 @@
-from abc import abstractmethod
 from typing import Any, Dict, List, Optional
 from typing import AsyncIterator
 from threading import Lock
+from asyncio import get_running_loop
 
 
 class SingletonMeta(type):
     # This is a thread-safe implementation of the Singleton pattern. Shamelessly stolen from
     # https://refactoring.guru/design-patterns/singleton/python/example#example-1
-    _instances: Dict[type, Any] = {}
+    _instances: Dict[str, Any] = {}
     _lock: Lock = Lock()
 
     def __call__(cls, *args: Any, **kwds: Any) -> Any:
         with cls._lock:
-            if cls not in cls._instances:
-                cls._instances[cls] = super().__call__(*args, **kwds)
-        return cls._instances[cls]
+            loop_class = str(hash(get_running_loop())) + str(cls)
+            if loop_class not in cls._instances:
+                cls._instances[loop_class] = super().__call__(*args, **kwds)
+        return cls._instances[loop_class]
 
 
 class SearchProvider(object, metaclass=SingletonMeta):