license: synchronize CPython license

The CPython license is a little out of date. Let's synchronize it.

Author: indygreg

LICENSE.cpython.txt

@@ -59,6 +59,17 @@ direction to make these releases possible.
 B. TERMS AND CONDITIONS FOR ACCESSING OR OTHERWISE USING PYTHON
 ===============================================================
 
+Python software and documentation are licensed under the
+Python Software Foundation License Version 2.
+
+Starting with Python 3.8.6, examples, recipes, and other code in
+the documentation are dual licensed under the PSF License Version 2
+and the Zero-Clause BSD license.
+
+Some software incorporated into Python is under different licenses.
+The licenses are listed with code falling under that license.
+
+
 PYTHON SOFTWARE FOUNDATION LICENSE VERSION 2
 --------------------------------------------
 
@@ -73,7 +84,7 @@ analyze, test, perform and/or display publicly, prepare derivative works,
 distribute, and otherwise use Python alone or in any derivative version,
 provided, however, that PSF's License Agreement and PSF's notice of copyright,
 i.e., "Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
-2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019 Python Software Foundation;
+2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022 Python Software Foundation;
 All Rights Reserved" are retained in Python alone or in any derivative version
 prepared by Licensee.
 
@@ -180,9 +191,9 @@ version prepared by Licensee.  Alternately, in lieu of CNRI's License
 Agreement, Licensee may substitute the following text (omitting the
 quotes): "Python 1.6.1 is made available subject to the terms and
 conditions in CNRI's License Agreement.  This Agreement together with
-Python 1.6.1 may be located on the Internet using the following
+Python 1.6.1 may be located on the internet using the following
 unique, persistent identifier (known as a handle): 1895.22/1013.  This
-Agreement may also be obtained from a proxy server on the Internet
+Agreement may also be obtained from a proxy server on the internet
 using the following URL: http://hdl.handle.net/1895.22/1013".
 
 3. In the event Licensee prepares a derivative work that is based on
@@ -253,6 +264,19 @@ WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
 OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
+ZERO-CLAUSE BSD LICENSE FOR CODE IN THE PYTHON DOCUMENTATION
+----------------------------------------------------------------------
+
+Permission to use, copy, modify, and/or distribute this software for any
+purpose with or without fee is hereby granted.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+PERFORMANCE OF THIS SOFTWARE.
 
 Licenses and Acknowledgements for Incorporated Software
 =======================================================
@@ -556,7 +580,7 @@ SipHash24
 ---------
 
 The file :file:`Python/pyhash.c` contains Marek Majkowski' implementation of
-Dan Bernstein's SipHash24 algorithm. The contains the following note::
+Dan Bernstein's SipHash24 algorithm. It contains the following note::
 
   <MIT License>
   Copyright (c) 2013  Marek Majkowski <[email protected]>
@@ -709,3 +733,39 @@ library unless the build is configured ``--with-system-libmpdec``::
    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
    OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
    SUCH DAMAGE.
+
+W3C C14N test suite
+-------------------
+
+The C14N 2.0 test suite in the :mod:`test` package
+(``Lib/test/xmltestdata/c14n-20/``) was retrieved from the W3C website at
+https://www.w3.org/TR/xml-c14n2-testcases/ and is distributed under the
+3-clause BSD license::
+
+   Copyright (c) 2013 W3C(R) (MIT, ERCIM, Keio, Beihang),
+   All Rights Reserved.
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions
+   are met:
+
+   * Redistributions of works must retain the original copyright notice,
+     this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the original copyright
+     notice, this list of conditions and the following disclaimer in the
+     documentation and/or other materials provided with the distribution.
+   * Neither the name of the W3C nor the names of its contributors may be
+     used to endorse or promote products derived from this work without
+     specific prior written permission.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.