shorten and fix casing of title

diff --git a/Doc/library/hashlib.rst b/Doc/library/hashlib.rst
index e33ef50a6e6b5f852049bd8833b8b7c110061337..9c6c4b973a08073ca248e8ba6aec502abd7675a8 100644 (file)
--- a/Doc/library/hashlib.rst
+++ b/Doc/library/hashlib.rst
@@ -153,8 +153,8 @@ A hash object has the following methods:
    compute the digests of strings that share 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