bpo-25821: Fix inaccuracy in threading.enumerate/is_alive documentation (GH-23192) (#26035)

(cherry picked from commit 12e7d10dfd28d4e26304e2c06b2e41c7418ec6f3)

Co-authored-by: Irit Katriel <iritkatriel@yahoo.com>
diff --git a/Lib/threading.py b/Lib/threading.py
index 4dcf847..fb70abd 100644
--- a/Lib/threading.py
+++ b/Lib/threading.py
@@ -1130,8 +1130,8 @@ def is_alive(self):
         """Return whether the thread is alive.
 
         This method returns True just before the run() method starts until just
-        after the run() method terminates. The module function enumerate()
-        returns a list of all alive threads.
+        after the run() method terminates. See also the module function
+        enumerate().
 
         """
         assert self._initialized, "Thread.__init__() not called"