Fixed issue with invoking _close() on closed event loop

redis/asyncio/connection.py

@@ -214,7 +214,13 @@ def __del__(self, _warnings: Any = warnings):
             _warnings.warn(
                 f"unclosed Connection {self!r}", ResourceWarning, source=self
             )
-            self._close()
+
+            try:
+                asyncio.get_running_loop()
+                self._close()
+            except RuntimeError:
+                # No actions been taken if pool already closed.
+                pass
 
     def _close(self):
         """

redis/asyncio/sentinel.py

@@ -29,11 +29,7 @@ def __init__(self, **kwargs):
         super().__init__(**kwargs)
 
     def __repr__(self):
-        pool = self.connection_pool
-        s = (
-            f"<{self.__class__.__module__}.{self.__class__.__name__}"
-            f"(service={pool.service_name}"
-        )
+        s = f"<{self.__class__.__module__}.{self.__class__.__name__}"
         if self.host:
             host_info = f",host={self.host},port={self.port}"
             s += host_info