From 3a92fce45aa5e2e0bd53a081213c725af76d72e6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?B=C3=A9n=C3=A9dikt=20Tran?=
 <10796600+picnixz@users.noreply.github.com>
Date: Fri, 10 Jan 2025 13:05:58 +0100
Subject: [PATCH 1/8] Improve import time of the `base64` module.

Importing `base64` is now up to six times faster.

The `re` module is now locally imported by `base64.b16decode`
and is no more implicitly exposed as `base64.re`.
---
 Lib/base64.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Lib/base64.py b/Lib/base64.py
index 61be4fb856e92c..ca17b9995ee658 100644
--- a/Lib/base64.py
+++ b/Lib/base64.py
@@ -4,7 +4,6 @@
 # Modified 30-Dec-2003 by Barry Warsaw to add full RFC 3548 support
 # Modified 22-May-2007 by Guido van Rossum to use bytes everywhere
 
-import re
 import struct
 import binascii
 
@@ -281,6 +280,8 @@ def b16decode(s, casefold=False):
     s is incorrectly padded or if there are non-alphabet characters present
     in the input.
     """
+    import re
+
     s = _bytes_from_decode_data(s)
     if casefold:
         s = s.upper()

From 0b52712c2bc4b7ff3bed98c0825ef2dbfabd33c1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?B=C3=A9n=C3=A9dikt=20Tran?=
 <10796600+picnixz@users.noreply.github.com>
Date: Fri, 10 Jan 2025 13:06:57 +0100
Subject: [PATCH 2/8] blurb

---
 .../next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst | 2 ++
 1 file changed, 2 insertions(+)
 create mode 100644 Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst

diff --git a/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst b/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst
new file mode 100644
index 00000000000000..11e66e98e57323
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst
@@ -0,0 +1,2 @@
+Improve import time of :mod:`base64` by a factor six. This is achieved by
+importing :mod:`re` on demand. Patch by Bénédikt Tran.

From d7b6253759ead4e28ba664d0950a0c3aaeb0036a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?B=C3=A9n=C3=A9dikt=20Tran?=
 <10796600+picnixz@users.noreply.github.com>
Date: Mon, 13 Jan 2025 13:22:54 +0100
Subject: [PATCH 3/8] Improve `base64.b16decode()` by a factor 10.

This entirely removes the needs to a regex.
---
 Lib/base64.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/Lib/base64.py b/Lib/base64.py
index ca17b9995ee658..5d78cc09f40cd3 100644
--- a/Lib/base64.py
+++ b/Lib/base64.py
@@ -280,12 +280,10 @@ def b16decode(s, casefold=False):
     s is incorrectly padded or if there are non-alphabet characters present
     in the input.
     """
-    import re
-
     s = _bytes_from_decode_data(s)
     if casefold:
         s = s.upper()
-    if re.search(b'[^0-9A-F]', s):
+    if s.translate(None, delete=b'0123456789ABCDEF'):
         raise binascii.Error('Non-base16 digit found')
     return binascii.unhexlify(s)
 

From 9e8fe5dbc099105c6768cb3588d15209412b86df Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?B=C3=A9n=C3=A9dikt=20Tran?=
 <10796600+picnixz@users.noreply.github.com>
Date: Mon, 13 Jan 2025 13:27:09 +0100
Subject: [PATCH 4/8] update NEWS

---
 .../Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst  | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst b/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst
index 11e66e98e57323..3d9f339693028a 100644
--- a/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst
+++ b/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst
@@ -1,2 +1,4 @@
-Improve import time of :mod:`base64` by a factor six. This is achieved by
-importing :mod:`re` on demand. Patch by Bénédikt Tran.
+Improve performance of :func:`base64.b16decode` by a factor ten by
+removing an un-necessary regular expression. Consequently, :mod:`re`
+is no more implicitly available as ``base64.re`` and import time of
+:mod:`base64` is improved by a factor six. Patch by Bénédikt Tran.

From 5be6178e771adbd7f197fc2fc461e63c89eb021b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?B=C3=A9n=C3=A9dikt=20Tran?=
 <10796600+picnixz@users.noreply.github.com>
Date: Mon, 13 Jan 2025 15:28:36 +0100
Subject: [PATCH 5/8] Update
 Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst

Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
---
 .../next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst b/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst
index 3d9f339693028a..e247557795d945 100644
--- a/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst
+++ b/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst
@@ -1,4 +1,4 @@
 Improve performance of :func:`base64.b16decode` by a factor ten by
-removing an un-necessary regular expression. Consequently, :mod:`re`
+removing an unnecessary regular expression. Consequently, :mod:`re`
 is no more implicitly available as ``base64.re`` and import time of
 :mod:`base64` is improved by a factor six. Patch by Bénédikt Tran.

From b36d9156fe89441f35fa6c50cc744b46174c095f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?B=C3=A9n=C3=A9dikt=20Tran?=
 <10796600+picnixz@users.noreply.github.com>
Date: Tue, 14 Jan 2025 10:25:20 +0100
Subject: [PATCH 6/8] add What's New entry

---
 Doc/whatsnew/3.14.rst | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/Doc/whatsnew/3.14.rst b/Doc/whatsnew/3.14.rst
index f365db37217e95..45888c552014ed 100644
--- a/Doc/whatsnew/3.14.rst
+++ b/Doc/whatsnew/3.14.rst
@@ -708,6 +708,17 @@ asyncio
   reduces memory usage.
   (Contributed by Kumar Aditya in :gh:`107803`.)
 
+
+base64
+------
+
+* Improve performance of :func:`base64.b16decode` by a factor ten by
+  removing an unnecessary regular expression. Consequently, :mod:`re`
+  is no more implicitly available as ``base64.re`` and import time of
+  :mod:`base64` is improved by a factor six.
+  (Contributed by Bénédikt Tran in :gh:`118761`.)
+
+
 io
 ---
 * :mod:`io` which provides the built-in :func:`open` makes less system calls

From 5562c81785ada71cd2f19de995a0c855aa476f0d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?B=C3=A9n=C3=A9dikt=20Tran?=
 <10796600+picnixz@users.noreply.github.com>
Date: Tue, 14 Jan 2025 13:43:01 +0100
Subject: [PATCH 7/8] Update Doc/whatsnew/3.14.rst

Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>
---
 Doc/whatsnew/3.14.rst | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/Doc/whatsnew/3.14.rst b/Doc/whatsnew/3.14.rst
index 45888c552014ed..21b69c02694373 100644
--- a/Doc/whatsnew/3.14.rst
+++ b/Doc/whatsnew/3.14.rst
@@ -712,11 +712,9 @@ asyncio
 base64
 ------
 
-* Improve performance of :func:`base64.b16decode` by a factor ten by
-  removing an unnecessary regular expression. Consequently, :mod:`re`
-  is no more implicitly available as ``base64.re`` and import time of
-  :mod:`base64` is improved by a factor six.
-  (Contributed by Bénédikt Tran in :gh:`118761`.)
+* Improve the performance of :func:`base64.b16decode` by up to ten times,
+  and reduce the import time of :mod:`base64` by up to six times.
+  (Contributed by Bénédikt Tran, Chris Markiewicz, and Adam Turner in :gh:`118761`.)
 
 
 io

From 82d18d7b522ed60b6b042d88e8046061f3dfd49f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?B=C3=A9n=C3=A9dikt=20Tran?=
 <10796600+picnixz@users.noreply.github.com>
Date: Tue, 14 Jan 2025 13:44:06 +0100
Subject: [PATCH 8/8] Update
 Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst

Co-authored-by: Adam Turner <9087854+AA-Turner@users.noreply.github.com>
---
 .../2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst       | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst b/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst
index e247557795d945..37c25cb2efd034 100644
--- a/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst
+++ b/Misc/NEWS.d/next/Library/2025-01-10-13-06-54.gh-issue-118761.f8oADD.rst
@@ -1,4 +1,5 @@
-Improve performance of :func:`base64.b16decode` by a factor ten by
-removing an unnecessary regular expression. Consequently, :mod:`re`
-is no more implicitly available as ``base64.re`` and import time of
-:mod:`base64` is improved by a factor six. Patch by Bénédikt Tran.
+Improve the performance of :func:`base64.b16decode` by up to ten times
+by more efficiently checking the byte-string for hexadecimal digits.
+Reduce the import time of :mod:`base64` by up to six times,
+by no longer importing :mod:`re`.
+Patch by Bénédikt Tran, Chris Markiewicz, and Adam Turner.