Add version{added,changed} for lock timeout support.

Doc/library/_thread.rst

@@ -109,6 +109,8 @@ It defines the following constants and functions:
    :meth:`Lock.acquire`. Specifiying a timeout greater than this value will
    raise an :exc:`OverflowError`.
 
+   .. versionadded:: 3.2
+
 
 Lock objects have the following methods:
 
@@ -132,6 +134,9 @@ Lock objects have the following methods:
    The return value is ``True`` if the lock is acquired successfully,
    ``False`` if not.
 
+   .. versionchanged:: 3.2
+      The *timeout* parameter is new.
+
 .. method:: lock.release()
 
    Releases the lock.  The lock must have been acquired earlier, but not

Doc/library/threading.rst

@@ -164,6 +164,7 @@ This module also defines the following constant:
    Specifiying a timeout greater than this value will raise an
    :exc:`OverflowError`.
 
+   .. versionadded:: 3.2
 
 Detailed interfaces for the objects are documented below.
 
@@ -382,6 +383,8 @@ All methods are executed atomically.
    The return value is ``True`` if the lock is acquired successfully,
    ``False`` if not (for example if the *timeout* expired).
 
+   .. versionchanged:: 3.2
+      The *timeout* parameter is new.
 
 .. method:: Lock.release()
 
@@ -439,6 +442,9 @@ pair) resets the lock to unlocked and allows another thread blocked in
    and as long as the lock cannot be acquired.  Return true if the lock has
    been acquired, false if the timeout has elapsed.
 
+   .. versionchanged:: 3.2
+      The *timeout* parameter is new.
+
 
 .. method:: RLock.release()