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1.. highlight:: none
2
3.. _history-and-license:
4
5*******************
6History and License
7*******************
8
9
10History of the software
11=======================
12
13Python was created in the early 1990s by Guido van Rossum at Stichting
14Mathematisch Centrum (CWI, see https://www.cwi.nl/) in the Netherlands as a
15successor of a language called ABC.  Guido remains Python's principal author,
16although it includes many contributions from others.
17
18In 1995, Guido continued his work on Python at the Corporation for National
19Research Initiatives (CNRI, see https://www.cnri.reston.va.us/) in Reston,
20Virginia where he released several versions of the software.
21
22In May 2000, Guido and the Python core development team moved to BeOpen.com to
23form the BeOpen PythonLabs team.  In October of the same year, the PythonLabs
24team moved to Digital Creations (now Zope Corporation; see
25https://www.zope.org/).  In 2001, the Python Software Foundation (PSF, see
26https://www.python.org/psf/) was formed, a non-profit organization created
27specifically to own Python-related Intellectual Property.  Zope Corporation is a
28sponsoring member of the PSF.
29
30All Python releases are Open Source (see https://opensource.org/ for the Open
31Source Definition). Historically, most, but not all, Python releases have also
32been GPL-compatible; the table below summarizes the various releases.
33
34+----------------+--------------+------------+------------+-----------------+
35| Release        | Derived from | Year       | Owner      | GPL compatible? |
36+================+==============+============+============+=================+
37| 0.9.0 thru 1.2 | n/a          | 1991-1995  | CWI        | yes             |
38+----------------+--------------+------------+------------+-----------------+
39| 1.3 thru 1.5.2 | 1.2          | 1995-1999  | CNRI       | yes             |
40+----------------+--------------+------------+------------+-----------------+
41| 1.6            | 1.5.2        | 2000       | CNRI       | no              |
42+----------------+--------------+------------+------------+-----------------+
43| 2.0            | 1.6          | 2000       | BeOpen.com | no              |
44+----------------+--------------+------------+------------+-----------------+
45| 1.6.1          | 1.6          | 2001       | CNRI       | no              |
46+----------------+--------------+------------+------------+-----------------+
47| 2.1            | 2.0+1.6.1    | 2001       | PSF        | no              |
48+----------------+--------------+------------+------------+-----------------+
49| 2.0.1          | 2.0+1.6.1    | 2001       | PSF        | yes             |
50+----------------+--------------+------------+------------+-----------------+
51| 2.1.1          | 2.1+2.0.1    | 2001       | PSF        | yes             |
52+----------------+--------------+------------+------------+-----------------+
53| 2.1.2          | 2.1.1        | 2002       | PSF        | yes             |
54+----------------+--------------+------------+------------+-----------------+
55| 2.1.3          | 2.1.2        | 2002       | PSF        | yes             |
56+----------------+--------------+------------+------------+-----------------+
57| 2.2 and above  | 2.1.1        | 2001-now   | PSF        | yes             |
58+----------------+--------------+------------+------------+-----------------+
59
60.. note::
61
62   GPL-compatible doesn't mean that we're distributing Python under the GPL.  All
63   Python licenses, unlike the GPL, let you distribute a modified version without
64   making your changes open source. The GPL-compatible licenses make it possible to
65   combine Python with other software that is released under the GPL; the others
66   don't.
67
68Thanks to the many outside volunteers who have worked under Guido's direction to
69make these releases possible.
70
71
72Terms and conditions for accessing or otherwise using Python
73============================================================
74
75Python software and documentation are licensed under the
76:ref:`PSF License Agreement <PSF-license>`.
77
78Starting with Python 3.8.6, examples, recipes, and other code in
79the documentation are dual licensed under the PSF License Agreement
80and the :ref:`Zero-Clause BSD license <BSD0>`.
81
82Some software incorporated into Python is under different licenses.
83The licenses are listed with code falling under that license.
84See :ref:`OtherLicenses` for an incomplete list of these licenses.
85
86
87.. _PSF-license:
88
89PSF LICENSE AGREEMENT FOR PYTHON |release|
90------------------------------------------
91
92.. parsed-literal::
93
94   1. This LICENSE AGREEMENT is between the Python Software Foundation ("PSF"), and
95      the Individual or Organization ("Licensee") accessing and otherwise using Python
96      |release| software in source or binary form and its associated documentation.
97
98   2. Subject to the terms and conditions of this License Agreement, PSF hereby
99      grants Licensee a nonexclusive, royalty-free, world-wide license to reproduce,
100      analyze, test, perform and/or display publicly, prepare derivative works,
101      distribute, and otherwise use Python |release| alone or in any derivative
102      version, provided, however, that PSF's License Agreement and PSF's notice of
103      copyright, i.e., "Copyright © 2001-2022 Python Software Foundation; All Rights
104      Reserved" are retained in Python |release| alone or in any derivative version
105      prepared by Licensee.
106
107   3. In the event Licensee prepares a derivative work that is based on or
108      incorporates Python |release| or any part thereof, and wants to make the
109      derivative work available to others as provided herein, then Licensee hereby
110      agrees to include in any such work a brief summary of the changes made to Python
111      |release|.
112
113   4. PSF is making Python |release| available to Licensee on an "AS IS" basis.
114      PSF MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED.  BY WAY OF
115      EXAMPLE, BUT NOT LIMITATION, PSF MAKES NO AND DISCLAIMS ANY REPRESENTATION OR
116      WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR THAT THE
117      USE OF PYTHON |release| WILL NOT INFRINGE ANY THIRD PARTY RIGHTS.
118
119   5. PSF SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON |release|
120      FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS A RESULT OF
121      MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON |release|, OR ANY DERIVATIVE
122      THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
123
124   6. This License Agreement will automatically terminate upon a material breach of
125      its terms and conditions.
126
127   7. Nothing in this License Agreement shall be deemed to create any relationship
128      of agency, partnership, or joint venture between PSF and Licensee.  This License
129      Agreement does not grant permission to use PSF trademarks or trade name in a
130      trademark sense to endorse or promote products or services of Licensee, or any
131      third party.
132
133   8. By copying, installing or otherwise using Python |release|, Licensee agrees
134      to be bound by the terms and conditions of this License Agreement.
135
136
137BEOPEN.COM LICENSE AGREEMENT FOR PYTHON 2.0
138-------------------------------------------
139
140BEOPEN PYTHON OPEN SOURCE LICENSE AGREEMENT VERSION 1
141
142.. parsed-literal::
143
144   1. This LICENSE AGREEMENT is between BeOpen.com ("BeOpen"), having an office at
145      160 Saratoga Avenue, Santa Clara, CA 95051, and the Individual or Organization
146      ("Licensee") accessing and otherwise using this software in source or binary
147      form and its associated documentation ("the Software").
148
149   2. Subject to the terms and conditions of this BeOpen Python License Agreement,
150      BeOpen hereby grants Licensee a non-exclusive, royalty-free, world-wide license
151      to reproduce, analyze, test, perform and/or display publicly, prepare derivative
152      works, distribute, and otherwise use the Software alone or in any derivative
153      version, provided, however, that the BeOpen Python License is retained in the
154      Software, alone or in any derivative version prepared by Licensee.
155
156   3. BeOpen is making the Software available to Licensee on an "AS IS" basis.
157      BEOPEN MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED.  BY WAY OF
158      EXAMPLE, BUT NOT LIMITATION, BEOPEN MAKES NO AND DISCLAIMS ANY REPRESENTATION OR
159      WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR THAT THE
160      USE OF THE SOFTWARE WILL NOT INFRINGE ANY THIRD PARTY RIGHTS.
161
162   4. BEOPEN SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF THE SOFTWARE FOR
163      ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS A RESULT OF USING,
164      MODIFYING OR DISTRIBUTING THE SOFTWARE, OR ANY DERIVATIVE THEREOF, EVEN IF
165      ADVISED OF THE POSSIBILITY THEREOF.
166
167   5. This License Agreement will automatically terminate upon a material breach of
168      its terms and conditions.
169
170   6. This License Agreement shall be governed by and interpreted in all respects
171      by the law of the State of California, excluding conflict of law provisions.
172      Nothing in this License Agreement shall be deemed to create any relationship of
173      agency, partnership, or joint venture between BeOpen and Licensee.  This License
174      Agreement does not grant permission to use BeOpen trademarks or trade names in a
175      trademark sense to endorse or promote products or services of Licensee, or any
176      third party.  As an exception, the "BeOpen Python" logos available at
177      http://www.pythonlabs.com/logos.html may be used according to the permissions
178      granted on that web page.
179
180   7. By copying, installing or otherwise using the software, Licensee agrees to be
181      bound by the terms and conditions of this License Agreement.
182
183
184CNRI LICENSE AGREEMENT FOR PYTHON 1.6.1
185---------------------------------------
186
187.. parsed-literal::
188
189   1. This LICENSE AGREEMENT is between the Corporation for National Research
190      Initiatives, having an office at 1895 Preston White Drive, Reston, VA 20191
191      ("CNRI"), and the Individual or Organization ("Licensee") accessing and
192      otherwise using Python 1.6.1 software in source or binary form and its
193      associated documentation.
194
195   2. Subject to the terms and conditions of this License Agreement, CNRI hereby
196      grants Licensee a nonexclusive, royalty-free, world-wide license to reproduce,
197      analyze, test, perform and/or display publicly, prepare derivative works,
198      distribute, and otherwise use Python 1.6.1 alone or in any derivative version,
199      provided, however, that CNRI's License Agreement and CNRI's notice of copyright,
200      i.e., "Copyright © 1995-2001 Corporation for National Research Initiatives; All
201      Rights Reserved" are retained in Python 1.6.1 alone or in any derivative version
202      prepared by Licensee.  Alternately, in lieu of CNRI's License Agreement,
203      Licensee may substitute the following text (omitting the quotes): "Python 1.6.1
204      is made available subject to the terms and conditions in CNRI's License
205      Agreement.  This Agreement together with Python 1.6.1 may be located on the
206      internet using the following unique, persistent identifier (known as a handle):
207      1895.22/1013.  This Agreement may also be obtained from a proxy server on the
208      internet using the following URL: http://hdl.handle.net/1895.22/1013."
209
210   3. In the event Licensee prepares a derivative work that is based on or
211      incorporates Python 1.6.1 or any part thereof, and wants to make the derivative
212      work available to others as provided herein, then Licensee hereby agrees to
213      include in any such work a brief summary of the changes made to Python 1.6.1.
214
215   4. CNRI is making Python 1.6.1 available to Licensee on an "AS IS" basis.  CNRI
216      MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED.  BY WAY OF EXAMPLE,
217      BUT NOT LIMITATION, CNRI MAKES NO AND DISCLAIMS ANY REPRESENTATION OR WARRANTY
218      OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF
219      PYTHON 1.6.1 WILL NOT INFRINGE ANY THIRD PARTY RIGHTS.
220
221   5. CNRI SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON 1.6.1 FOR
222      ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS A RESULT OF
223      MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON 1.6.1, OR ANY DERIVATIVE
224      THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
225
226   6. This License Agreement will automatically terminate upon a material breach of
227      its terms and conditions.
228
229   7. This License Agreement shall be governed by the federal intellectual property
230      law of the United States, including without limitation the federal copyright
231      law, and, to the extent such U.S. federal law does not apply, by the law of the
232      Commonwealth of Virginia, excluding Virginia's conflict of law provisions.
233      Notwithstanding the foregoing, with regard to derivative works based on Python
234      1.6.1 that incorporate non-separable material that was previously distributed
235      under the GNU General Public License (GPL), the law of the Commonwealth of
236      Virginia shall govern this License Agreement only as to issues arising under or
237      with respect to Paragraphs 4, 5, and 7 of this License Agreement.  Nothing in
238      this License Agreement shall be deemed to create any relationship of agency,
239      partnership, or joint venture between CNRI and Licensee.  This License Agreement
240      does not grant permission to use CNRI trademarks or trade name in a trademark
241      sense to endorse or promote products or services of Licensee, or any third
242      party.
243
244   8. By clicking on the "ACCEPT" button where indicated, or by copying, installing
245      or otherwise using Python 1.6.1, Licensee agrees to be bound by the terms and
246      conditions of this License Agreement.
247
248
249CWI LICENSE AGREEMENT FOR PYTHON 0.9.0 THROUGH 1.2
250--------------------------------------------------
251
252.. parsed-literal::
253
254   Copyright © 1991 - 1995, Stichting Mathematisch Centrum Amsterdam, The
255   Netherlands.  All rights reserved.
256
257   Permission to use, copy, modify, and distribute this software and its
258   documentation for any purpose and without fee is hereby granted, provided that
259   the above copyright notice appear in all copies and that both that copyright
260   notice and this permission notice appear in supporting documentation, and that
261   the name of Stichting Mathematisch Centrum or CWI not be used in advertising or
262   publicity pertaining to distribution of the software without specific, written
263   prior permission.
264
265   STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
266   SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
267   EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE FOR ANY SPECIAL, INDIRECT
268   OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
269   DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
270   ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
271   SOFTWARE.
272
273
274.. _BSD0:
275
276ZERO-CLAUSE BSD LICENSE FOR CODE IN THE PYTHON |release| DOCUMENTATION
277----------------------------------------------------------------------
278
279.. parsed-literal::
280
281    Permission to use, copy, modify, and/or distribute this software for any
282    purpose with or without fee is hereby granted.
283
284    THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
285    REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
286    AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
287    INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
288    LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
289    OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
290    PERFORMANCE OF THIS SOFTWARE.
291
292
293.. _OtherLicenses:
294
295Licenses and Acknowledgements for Incorporated Software
296=======================================================
297
298This section is an incomplete, but growing list of licenses and acknowledgements
299for third-party software incorporated in the Python distribution.
300
301
302Mersenne Twister
303----------------
304
305The :mod:`_random` module includes code based on a download from
306http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/MT2002/emt19937ar.html. The following are
307the verbatim comments from the original code::
308
309   A C-program for MT19937, with initialization improved 2002/1/26.
310   Coded by Takuji Nishimura and Makoto Matsumoto.
311
312   Before using, initialize the state by using init_genrand(seed)
313   or init_by_array(init_key, key_length).
314
315   Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura,
316   All rights reserved.
317
318   Redistribution and use in source and binary forms, with or without
319   modification, are permitted provided that the following conditions
320   are met:
321
322    1. Redistributions of source code must retain the above copyright
323       notice, this list of conditions and the following disclaimer.
324
325    2. Redistributions in binary form must reproduce the above copyright
326       notice, this list of conditions and the following disclaimer in the
327       documentation and/or other materials provided with the distribution.
328
329    3. The names of its contributors may not be used to endorse or promote
330       products derived from this software without specific prior written
331       permission.
332
333   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
334   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
335   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
336   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
337   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
338   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
339   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
340   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
341   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
342   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
343   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
344
345
346   Any feedback is very welcome.
347   http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html
348   email: m-mat @ math.sci.hiroshima-u.ac.jp (remove space)
349
350
351Sockets
352-------
353
354The :mod:`socket` module uses the functions, :func:`getaddrinfo`, and
355:func:`getnameinfo`, which are coded in separate source files from the WIDE
356Project, http://www.wide.ad.jp/. ::
357
358   Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
359   All rights reserved.
360
361   Redistribution and use in source and binary forms, with or without
362   modification, are permitted provided that the following conditions
363   are met:
364   1. Redistributions of source code must retain the above copyright
365      notice, this list of conditions and the following disclaimer.
366   2. Redistributions in binary form must reproduce the above copyright
367      notice, this list of conditions and the following disclaimer in the
368      documentation and/or other materials provided with the distribution.
369   3. Neither the name of the project nor the names of its contributors
370      may be used to endorse or promote products derived from this software
371      without specific prior written permission.
372
373   THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
374   ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
375   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
376   ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
377   FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
378   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
379   OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
380   HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
381   LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
382   OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
383   SUCH DAMAGE.
384
385
386Asynchronous socket services
387----------------------------
388
389The :mod:`asynchat` and :mod:`asyncore` modules contain the following notice::
390
391   Copyright 1996 by Sam Rushing
392
393                           All Rights Reserved
394
395   Permission to use, copy, modify, and distribute this software and
396   its documentation for any purpose and without fee is hereby
397   granted, provided that the above copyright notice appear in all
398   copies and that both that copyright notice and this permission
399   notice appear in supporting documentation, and that the name of Sam
400   Rushing not be used in advertising or publicity pertaining to
401   distribution of the software without specific, written prior
402   permission.
403
404   SAM RUSHING DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
405   INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN
406   NO EVENT SHALL SAM RUSHING BE LIABLE FOR ANY SPECIAL, INDIRECT OR
407   CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
408   OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
409   NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
410   CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
411
412
413Cookie management
414-----------------
415
416The :mod:`http.cookies` module contains the following notice::
417
418   Copyright 2000 by Timothy O'Malley <timo@alum.mit.edu>
419
420                  All Rights Reserved
421
422   Permission to use, copy, modify, and distribute this software
423   and its documentation for any purpose and without fee is hereby
424   granted, provided that the above copyright notice appear in all
425   copies and that both that copyright notice and this permission
426   notice appear in supporting documentation, and that the name of
427   Timothy O'Malley  not be used in advertising or publicity
428   pertaining to distribution of the software without specific, written
429   prior permission.
430
431   Timothy O'Malley DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
432   SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
433   AND FITNESS, IN NO EVENT SHALL Timothy O'Malley BE LIABLE FOR
434   ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
435   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
436   WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
437   ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
438   PERFORMANCE OF THIS SOFTWARE.
439
440
441Execution tracing
442-----------------
443
444The :mod:`trace` module contains the following notice::
445
446   portions copyright 2001, Autonomous Zones Industries, Inc., all rights...
447   err...  reserved and offered to the public under the terms of the
448   Python 2.2 license.
449   Author: Zooko O'Whielacronx
450   http://zooko.com/
451   mailto:zooko@zooko.com
452
453   Copyright 2000, Mojam Media, Inc., all rights reserved.
454   Author: Skip Montanaro
455
456   Copyright 1999, Bioreason, Inc., all rights reserved.
457   Author: Andrew Dalke
458
459   Copyright 1995-1997, Automatrix, Inc., all rights reserved.
460   Author: Skip Montanaro
461
462   Copyright 1991-1995, Stichting Mathematisch Centrum, all rights reserved.
463
464
465   Permission to use, copy, modify, and distribute this Python software and
466   its associated documentation for any purpose without fee is hereby
467   granted, provided that the above copyright notice appears in all copies,
468   and that both that copyright notice and this permission notice appear in
469   supporting documentation, and that the name of neither Automatrix,
470   Bioreason or Mojam Media be used in advertising or publicity pertaining to
471   distribution of the software without specific, written prior permission.
472
473
474UUencode and UUdecode functions
475-------------------------------
476
477The :mod:`uu` module contains the following notice::
478
479   Copyright 1994 by Lance Ellinghouse
480   Cathedral City, California Republic, United States of America.
481                          All Rights Reserved
482   Permission to use, copy, modify, and distribute this software and its
483   documentation for any purpose and without fee is hereby granted,
484   provided that the above copyright notice appear in all copies and that
485   both that copyright notice and this permission notice appear in
486   supporting documentation, and that the name of Lance Ellinghouse
487   not be used in advertising or publicity pertaining to distribution
488   of the software without specific, written prior permission.
489   LANCE ELLINGHOUSE DISCLAIMS ALL WARRANTIES WITH REGARD TO
490   THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
491   FITNESS, IN NO EVENT SHALL LANCE ELLINGHOUSE CENTRUM BE LIABLE
492   FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
493   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
494   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
495   OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
496
497   Modified by Jack Jansen, CWI, July 1995:
498   - Use binascii module to do the actual line-by-line conversion
499     between ascii and binary. This results in a 1000-fold speedup. The C
500     version is still 5 times faster, though.
501   - Arguments more compliant with Python standard
502
503
504XML Remote Procedure Calls
505--------------------------
506
507The :mod:`xmlrpc.client` module contains the following notice::
508
509       The XML-RPC client interface is
510
511   Copyright (c) 1999-2002 by Secret Labs AB
512   Copyright (c) 1999-2002 by Fredrik Lundh
513
514   By obtaining, using, and/or copying this software and/or its
515   associated documentation, you agree that you have read, understood,
516   and will comply with the following terms and conditions:
517
518   Permission to use, copy, modify, and distribute this software and
519   its associated documentation for any purpose and without fee is
520   hereby granted, provided that the above copyright notice appears in
521   all copies, and that both that copyright notice and this permission
522   notice appear in supporting documentation, and that the name of
523   Secret Labs AB or the author not be used in advertising or publicity
524   pertaining to distribution of the software without specific, written
525   prior permission.
526
527   SECRET LABS AB AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD
528   TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANT-
529   ABILITY AND FITNESS.  IN NO EVENT SHALL SECRET LABS AB OR THE AUTHOR
530   BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY
531   DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
532   WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
533   ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
534   OF THIS SOFTWARE.
535
536
537test_epoll
538----------
539
540The :mod:`test_epoll` module contains the following notice::
541
542  Copyright (c) 2001-2006 Twisted Matrix Laboratories.
543
544  Permission is hereby granted, free of charge, to any person obtaining
545  a copy of this software and associated documentation files (the
546  "Software"), to deal in the Software without restriction, including
547  without limitation the rights to use, copy, modify, merge, publish,
548  distribute, sublicense, and/or sell copies of the Software, and to
549  permit persons to whom the Software is furnished to do so, subject to
550  the following conditions:
551
552  The above copyright notice and this permission notice shall be
553  included in all copies or substantial portions of the Software.
554
555  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
556  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
557  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
558  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
559  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
560  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
561  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
562
563Select kqueue
564-------------
565
566The :mod:`select` module contains the following notice for the kqueue
567interface::
568
569  Copyright (c) 2000 Doug White, 2006 James Knight, 2007 Christian Heimes
570  All rights reserved.
571
572  Redistribution and use in source and binary forms, with or without
573  modification, are permitted provided that the following conditions
574  are met:
575  1. Redistributions of source code must retain the above copyright
576     notice, this list of conditions and the following disclaimer.
577  2. Redistributions in binary form must reproduce the above copyright
578     notice, this list of conditions and the following disclaimer in the
579     documentation and/or other materials provided with the distribution.
580
581  THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
582  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
583  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
584  ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
585  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
586  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
587  OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
588  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
589  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
590  OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
591  SUCH DAMAGE.
592
593
594SipHash24
595---------
596
597The file :file:`Python/pyhash.c` contains Marek Majkowski' implementation of
598Dan Bernstein's SipHash24 algorithm. It contains the following note::
599
600  <MIT License>
601  Copyright (c) 2013  Marek Majkowski <marek@popcount.org>
602
603  Permission is hereby granted, free of charge, to any person obtaining a copy
604  of this software and associated documentation files (the "Software"), to deal
605  in the Software without restriction, including without limitation the rights
606  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
607  copies of the Software, and to permit persons to whom the Software is
608  furnished to do so, subject to the following conditions:
609
610  The above copyright notice and this permission notice shall be included in
611  all copies or substantial portions of the Software.
612  </MIT License>
613
614  Original location:
615     https://github.com/majek/csiphash/
616
617  Solution inspired by code from:
618     Samuel Neves (supercop/crypto_auth/siphash24/little)
619     djb (supercop/crypto_auth/siphash24/little2)
620     Jean-Philippe Aumasson (https://131002.net/siphash/siphash24.c)
621
622
623strtod and dtoa
624---------------
625
626The file :file:`Python/dtoa.c`, which supplies C functions dtoa and
627strtod for conversion of C doubles to and from strings, is derived
628from the file of the same name by David M. Gay, currently available
629from http://www.netlib.org/fp/.  The original file, as retrieved on
630March 16, 2009, contains the following copyright and licensing
631notice::
632
633   /****************************************************************
634    *
635    * The author of this software is David M. Gay.
636    *
637    * Copyright (c) 1991, 2000, 2001 by Lucent Technologies.
638    *
639    * Permission to use, copy, modify, and distribute this software for any
640    * purpose without fee is hereby granted, provided that this entire notice
641    * is included in all copies of any software which is or includes a copy
642    * or modification of this software and in all copies of the supporting
643    * documentation for such software.
644    *
645    * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
646    * WARRANTY.  IN PARTICULAR, NEITHER THE AUTHOR NOR LUCENT MAKES ANY
647    * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
648    * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
649    *
650    ***************************************************************/
651
652
653OpenSSL
654-------
655
656The modules :mod:`hashlib`, :mod:`posix`, :mod:`ssl`, :mod:`crypt` use
657the OpenSSL library for added performance if made available by the
658operating system. Additionally, the Windows and macOS installers for
659Python may include a copy of the OpenSSL libraries, so we include a copy
660of the OpenSSL license here::
661
662
663  LICENSE ISSUES
664  ==============
665
666  The OpenSSL toolkit stays under a dual license, i.e. both the conditions of
667  the OpenSSL License and the original SSLeay license apply to the toolkit.
668  See below for the actual license texts. Actually both licenses are BSD-style
669  Open Source licenses. In case of any license issues related to OpenSSL
670  please contact openssl-core@openssl.org.
671
672  OpenSSL License
673  ---------------
674
675    /* ====================================================================
676     * Copyright (c) 1998-2008 The OpenSSL Project.  All rights reserved.
677     *
678     * Redistribution and use in source and binary forms, with or without
679     * modification, are permitted provided that the following conditions
680     * are met:
681     *
682     * 1. Redistributions of source code must retain the above copyright
683     *    notice, this list of conditions and the following disclaimer.
684     *
685     * 2. Redistributions in binary form must reproduce the above copyright
686     *    notice, this list of conditions and the following disclaimer in
687     *    the documentation and/or other materials provided with the
688     *    distribution.
689     *
690     * 3. All advertising materials mentioning features or use of this
691     *    software must display the following acknowledgment:
692     *    "This product includes software developed by the OpenSSL Project
693     *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
694     *
695     * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
696     *    endorse or promote products derived from this software without
697     *    prior written permission. For written permission, please contact
698     *    openssl-core@openssl.org.
699     *
700     * 5. Products derived from this software may not be called "OpenSSL"
701     *    nor may "OpenSSL" appear in their names without prior written
702     *    permission of the OpenSSL Project.
703     *
704     * 6. Redistributions of any form whatsoever must retain the following
705     *    acknowledgment:
706     *    "This product includes software developed by the OpenSSL Project
707     *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
708     *
709     * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
710     * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
711     * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
712     * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
713     * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
714     * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
715     * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
716     * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
717     * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
718     * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
719     * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
720     * OF THE POSSIBILITY OF SUCH DAMAGE.
721     * ====================================================================
722     *
723     * This product includes cryptographic software written by Eric Young
724     * (eay@cryptsoft.com).  This product includes software written by Tim
725     * Hudson (tjh@cryptsoft.com).
726     *
727     */
728
729 Original SSLeay License
730 -----------------------
731
732    /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
733     * All rights reserved.
734     *
735     * This package is an SSL implementation written
736     * by Eric Young (eay@cryptsoft.com).
737     * The implementation was written so as to conform with Netscapes SSL.
738     *
739     * This library is free for commercial and non-commercial use as long as
740     * the following conditions are aheared to.  The following conditions
741     * apply to all code found in this distribution, be it the RC4, RSA,
742     * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
743     * included with this distribution is covered by the same copyright terms
744     * except that the holder is Tim Hudson (tjh@cryptsoft.com).
745     *
746     * Copyright remains Eric Young's, and as such any Copyright notices in
747     * the code are not to be removed.
748     * If this package is used in a product, Eric Young should be given attribution
749     * as the author of the parts of the library used.
750     * This can be in the form of a textual message at program startup or
751     * in documentation (online or textual) provided with the package.
752     *
753     * Redistribution and use in source and binary forms, with or without
754     * modification, are permitted provided that the following conditions
755     * are met:
756     * 1. Redistributions of source code must retain the copyright
757     *    notice, this list of conditions and the following disclaimer.
758     * 2. Redistributions in binary form must reproduce the above copyright
759     *    notice, this list of conditions and the following disclaimer in the
760     *    documentation and/or other materials provided with the distribution.
761     * 3. All advertising materials mentioning features or use of this software
762     *    must display the following acknowledgement:
763     *    "This product includes cryptographic software written by
764     *     Eric Young (eay@cryptsoft.com)"
765     *    The word 'cryptographic' can be left out if the rouines from the library
766     *    being used are not cryptographic related :-).
767     * 4. If you include any Windows specific code (or a derivative thereof) from
768     *    the apps directory (application code) you must include an acknowledgement:
769     *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
770     *
771     * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
772     * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
773     * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
774     * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
775     * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
776     * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
777     * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
778     * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
779     * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
780     * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
781     * SUCH DAMAGE.
782     *
783     * The licence and distribution terms for any publically available version or
784     * derivative of this code cannot be changed.  i.e. this code cannot simply be
785     * copied and put under another distribution licence
786     * [including the GNU Public Licence.]
787     */
788
789
790expat
791-----
792
793The :mod:`pyexpat` extension is built using an included copy of the expat
794sources unless the build is configured ``--with-system-expat``::
795
796  Copyright (c) 1998, 1999, 2000 Thai Open Source Software Center Ltd
797                                 and Clark Cooper
798
799  Permission is hereby granted, free of charge, to any person obtaining
800  a copy of this software and associated documentation files (the
801  "Software"), to deal in the Software without restriction, including
802  without limitation the rights to use, copy, modify, merge, publish,
803  distribute, sublicense, and/or sell copies of the Software, and to
804  permit persons to whom the Software is furnished to do so, subject to
805  the following conditions:
806
807  The above copyright notice and this permission notice shall be included
808  in all copies or substantial portions of the Software.
809
810  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
811  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
812  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
813  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
814  CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
815  TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
816  SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
817
818
819libffi
820------
821
822The :mod:`_ctypes` extension is built using an included copy of the libffi
823sources unless the build is configured ``--with-system-libffi``::
824
825   Copyright (c) 1996-2008  Red Hat, Inc and others.
826
827   Permission is hereby granted, free of charge, to any person obtaining
828   a copy of this software and associated documentation files (the
829   ``Software''), to deal in the Software without restriction, including
830   without limitation the rights to use, copy, modify, merge, publish,
831   distribute, sublicense, and/or sell copies of the Software, and to
832   permit persons to whom the Software is furnished to do so, subject to
833   the following conditions:
834
835   The above copyright notice and this permission notice shall be included
836   in all copies or substantial portions of the Software.
837
838   THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND,
839   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
840   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
841   NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
842   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
843   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
844   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
845   DEALINGS IN THE SOFTWARE.
846
847
848zlib
849----
850
851The :mod:`zlib` extension is built using an included copy of the zlib
852sources if the zlib version found on the system is too old to be
853used for the build::
854
855  Copyright (C) 1995-2011 Jean-loup Gailly and Mark Adler
856
857  This software is provided 'as-is', without any express or implied
858  warranty.  In no event will the authors be held liable for any damages
859  arising from the use of this software.
860
861  Permission is granted to anyone to use this software for any purpose,
862  including commercial applications, and to alter it and redistribute it
863  freely, subject to the following restrictions:
864
865  1. The origin of this software must not be misrepresented; you must not
866     claim that you wrote the original software. If you use this software
867     in a product, an acknowledgment in the product documentation would be
868     appreciated but is not required.
869
870  2. Altered source versions must be plainly marked as such, and must not be
871     misrepresented as being the original software.
872
873  3. This notice may not be removed or altered from any source distribution.
874
875  Jean-loup Gailly        Mark Adler
876  jloup@gzip.org          madler@alumni.caltech.edu
877
878
879cfuhash
880-------
881
882The implementation of the hash table used by the :mod:`tracemalloc` is based
883on the cfuhash project::
884
885   Copyright (c) 2005 Don Owens
886   All rights reserved.
887
888   This code is released under the BSD license:
889
890   Redistribution and use in source and binary forms, with or without
891   modification, are permitted provided that the following conditions
892   are met:
893
894     * Redistributions of source code must retain the above copyright
895       notice, this list of conditions and the following disclaimer.
896
897     * Redistributions in binary form must reproduce the above
898       copyright notice, this list of conditions and the following
899       disclaimer in the documentation and/or other materials provided
900       with the distribution.
901
902     * Neither the name of the author nor the names of its
903       contributors may be used to endorse or promote products derived
904       from this software without specific prior written permission.
905
906   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
907   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
908   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
909   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
910   COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
911   INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
912   (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
913   SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
914   HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
915   STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
916   ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
917   OF THE POSSIBILITY OF SUCH DAMAGE.
918
919
920libmpdec
921--------
922
923The :mod:`_decimal` module is built using an included copy of the libmpdec
924library unless the build is configured ``--with-system-libmpdec``::
925
926   Copyright (c) 2008-2020 Stefan Krah. All rights reserved.
927
928   Redistribution and use in source and binary forms, with or without
929   modification, are permitted provided that the following conditions
930   are met:
931
932   1. Redistributions of source code must retain the above copyright
933      notice, this list of conditions and the following disclaimer.
934
935   2. Redistributions in binary form must reproduce the above copyright
936      notice, this list of conditions and the following disclaimer in the
937      documentation and/or other materials provided with the distribution.
938
939   THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND
940   ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
941   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
942   ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
943   FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
944   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
945   OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
946   HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
947   LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
948   OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
949   SUCH DAMAGE.
950
951
952W3C C14N test suite
953-------------------
954
955The C14N 2.0 test suite in the :mod:`test` package
956(``Lib/test/xmltestdata/c14n-20/``) was retrieved from the W3C website at
957https://www.w3.org/TR/xml-c14n2-testcases/ and is distributed under the
9583-clause BSD license::
959
960   Copyright (c) 2013 W3C(R) (MIT, ERCIM, Keio, Beihang),
961   All Rights Reserved.
962
963   Redistribution and use in source and binary forms, with or without
964   modification, are permitted provided that the following conditions
965   are met:
966
967   * Redistributions of works must retain the original copyright notice,
968     this list of conditions and the following disclaimer.
969   * Redistributions in binary form must reproduce the original copyright
970     notice, this list of conditions and the following disclaimer in the
971     documentation and/or other materials provided with the distribution.
972   * Neither the name of the W3C nor the names of its contributors may be
973     used to endorse or promote products derived from this work without
974     specific prior written permission.
975
976   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
977   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
978   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
979   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
980   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
981   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
982   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
983   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
984   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
985   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
986   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
987