Issue 10789: Correct threading.Lock.acquire signature.
diff --git a/Doc/library/threading.rst b/Doc/library/threading.rst
index 910e49d..c9ef294 100644
--- a/Doc/library/threading.rst
+++ b/Doc/library/threading.rst
@@ -365,7 +365,7 @@
 All methods are executed atomically.
 
 
-.. method:: Lock.acquire(blocking=True)
+.. method:: Lock.acquire([blocking])
 
    Acquire a lock, blocking or non-blocking.