shorten and fix casing of title

diff --git a/Doc/library/hashlib.rst b/Doc/library/hashlib.rst
index e0a877a71d0d0a60776c9933d58f7399b585c44c..84924229b8e4d0dcb21bc7e7f46bf04cb10257c4 100644 (file)
--- a/Doc/library/hashlib.rst
+++ b/Doc/library/hashlib.rst
@@ -176,8 +176,8 @@ A hash object has the following methods:
    compute the digests of data sharing a common initial substring.
 
 
-Key Derivation Function
------------------------
+Key derivation
+--------------
 
 Key derivation and key stretching algorithms are designed for secure password
 hashing. Naive algorithms such as ``sha1(password)`` are not resistant against