[3.8] bpo-36373: Fix deprecation warnings (GH-15889) (GH-15901)

https://bugs.python.org/issue36373
(cherry picked from commit 7264e92b718d307cc499b2f10eab7644b00f0499)

Co-authored-by: Andrew Svetlov <andrew.svetlov@gmail.com>
diff --git a/Lib/asyncio/locks.py b/Lib/asyncio/locks.py
index f63d4ce..d94daeb 100644
--- a/Lib/asyncio/locks.py
+++ b/Lib/asyncio/locks.py
@@ -332,7 +332,7 @@
                           DeprecationWarning, stacklevel=2)
 
         if lock is None:
-            lock = Lock(loop=self._loop)
+            lock = Lock(loop=loop)
         elif lock._loop is not self._loop:
             raise ValueError("loop argument must agree with lock")