Issue 14673: Add sys.implementation

in order to make algorithmic complexity attacks on (e.g.) web apps much more complicated.

The environment variable PYTHONHASHSEED and the new command line flag -R control this
behavior.

Closes #13402.

used with sys.setdlopenflags().

- Using the file role with {placeholders} is IMO clearer than fake
  Python code.

- The fact that sys.version[:3] gives '3.2' is a CPython detail and
  should not be advertised (see #9442), even if some stdlib modules
  currently rely on that detail.

sys.maxunicode is not called and thus does not return anything; it *is*
something.  (I checked the doc quickly to see if it tells that
expression return things but found nothing.)

I also removed markup that would just generate a useless link to the
enclosing section.

Also, point to the various alternatives.

Patch by Sijin Joseph.

The options listed in the table are now links to their documentation,
and the table uses compact markup to make it easier to read and edit.
First proposed in #10998.

svn+ssh://pythondev@svn.python.org/python/branches/py3k

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  r86521 | eric.araujo | 2010-11-18 17:38:46 +0100 (jeu., 18 nov. 2010) | 17 lines

  Fix usage of :option: in the docs (#9312).

  :option: is used to create a link to an option of python, not to mark
  up any instance of any arbitrary command-line option.  These were
  changed to ````.

  For modules which do have a command-line interface, lists of options
  have been properly marked up with the program/cmdoption directives
  combo.  Options defined in such blocks can be linked to with :option:
  later in the same file, they won’t link to an option of python.

  Finally, the markup of command-line fragments in optparse.rst has
  been cleaned to use ``x`` instead of ``"x"``, keeping that latter
  form for actual Python strings.

  Patch by Eli Bendersky and Éric Araujo.
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  r86632 | eric.araujo | 2010-11-21 04:09:17 +0100 (dim., 21 nov. 2010) | 2 lines

  Style edits in followup to r86521 (#9312)
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  r86823 | eric.araujo | 2010-11-27 00:31:07 +0100 (sam., 27 nov. 2010) | 2 lines

  Use link-generating markup (see #9312)
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  r86824 | eric.araujo | 2010-11-27 00:46:18 +0100 (sam., 27 nov. 2010) | 2 lines

  Rewrap long lines + minor edits
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  r87294 | eric.araujo | 2010-12-16 01:07:01 +0100 (jeu., 16 déc. 2010) | 2 lines

  No need to generate a link for something that’s just above.
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  r87296 | eric.araujo | 2010-12-16 01:23:30 +0100 (jeu., 16 déc. 2010) | 2 lines

  Advertise “python -m” instead of direct filename.
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  r87300 | eric.araujo | 2010-12-16 02:40:26 +0100 (jeu., 16 déc. 2010) | 2 lines

  Advertise “python -m test” over test.regrtest (r87296 followup)
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  r87302 | eric.araujo | 2010-12-16 03:10:11 +0100 (jeu., 16 déc. 2010) | 2 lines

  Add versionadded directive missing from r78983.
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UnicodeEncodeError.

Merged revisions 85572-85573,85606,85609-85622,85624,85626-85627,85629,85631,85633,85635-85636,85638-85639,85641-85642 via svnmerge from
svn+ssh://svn.python.org/python/branches/py3k

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  r85572 | georg.brandl | 2010-10-16 20:51:05 +0200 (Sa, 16 Okt 2010) | 1 line

  #10122: typo fix.
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  r85573 | georg.brandl | 2010-10-16 20:53:08 +0200 (Sa, 16 Okt 2010) | 1 line

  #10124: typo fix.
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  r85606 | georg.brandl | 2010-10-17 08:32:59 +0200 (So, 17 Okt 2010) | 1 line

  #10058: tweak wording about exception returns.
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  r85609 | georg.brandl | 2010-10-17 11:19:03 +0200 (So, 17 Okt 2010) | 1 line

  #8556: use less confusing mapping key in example.
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  r85610 | georg.brandl | 2010-10-17 11:23:05 +0200 (So, 17 Okt 2010) | 1 line

  #8686: remove potentially confusing wording that does not add any value.
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  r85611 | georg.brandl | 2010-10-17 11:33:24 +0200 (So, 17 Okt 2010) | 1 line

  #8811: small fixes to sqlite3 docs.
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  r85612 | georg.brandl | 2010-10-17 11:37:54 +0200 (So, 17 Okt 2010) | 1 line

  #8855: add shelve security warning.
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  r85613 | georg.brandl | 2010-10-17 11:43:35 +0200 (So, 17 Okt 2010) | 1 line

  Fix hmac docs: it takes and returns bytes, except for hexdigest().
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  r85614 | georg.brandl | 2010-10-17 11:46:11 +0200 (So, 17 Okt 2010) | 1 line

  #8968: add actual name of token constants.
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  r85615 | georg.brandl | 2010-10-17 12:05:13 +0200 (So, 17 Okt 2010) | 1 line

  #459007: merge info from PC/getpathp.c and using/windows.rst to document the forming of sys.path under Windows.
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  r85616 | georg.brandl | 2010-10-17 12:07:29 +0200 (So, 17 Okt 2010) | 1 line

  Fix copy-paste error in example.
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  r85617 | georg.brandl | 2010-10-17 12:09:06 +0200 (So, 17 Okt 2010) | 1 line

  #5212: md5 weaknesses do not affect hmac, so remove the note about that.
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  r85618 | georg.brandl | 2010-10-17 12:14:38 +0200 (So, 17 Okt 2010) | 1 line

  #9086: correct wrong terminology about linking with pythonXY.dll.
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  r85619 | georg.brandl | 2010-10-17 12:15:50 +0200 (So, 17 Okt 2010) | 1 line

  Make file names consistent.
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  r85620 | georg.brandl | 2010-10-17 12:22:28 +0200 (So, 17 Okt 2010) | 1 line

  Remove second parser module example; it referred to non-readily-available example files, and this kind of discovery is much better done with the AST nowadays anyway.
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  r85621 | georg.brandl | 2010-10-17 12:24:54 +0200 (So, 17 Okt 2010) | 1 line

  #9105: move pickle warning to a bit more prominent location.
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  r85622 | georg.brandl | 2010-10-17 12:28:04 +0200 (So, 17 Okt 2010) | 1 line

  #9112: document error() and exit() methods of ArgumentParser.
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  r85624 | georg.brandl | 2010-10-17 12:34:28 +0200 (So, 17 Okt 2010) | 1 line

  Some markup and style fixes in argparse docs.
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  r85626 | georg.brandl | 2010-10-17 12:38:20 +0200 (So, 17 Okt 2010) | 1 line

  #9117: fix syntax for class definition.
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  r85627 | georg.brandl | 2010-10-17 12:44:11 +0200 (So, 17 Okt 2010) | 1 line

  #9138: reword introduction to classes in Python.
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  r85629 | georg.brandl | 2010-10-17 12:51:45 +0200 (So, 17 Okt 2010) | 1 line

  #5962: clarify sys.exit() vs. threads.
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  r85631 | georg.brandl | 2010-10-17 12:53:54 +0200 (So, 17 Okt 2010) | 1 line

  Fix capitalization.
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  r85633 | georg.brandl | 2010-10-17 12:59:41 +0200 (So, 17 Okt 2010) | 1 line

  #9204: remove mentions of removed types in the types module.
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  r85635 | georg.brandl | 2010-10-17 13:03:22 +0200 (So, 17 Okt 2010) | 1 line

  #5121: fix claims about default values leading to segfaults.
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  r85636 | georg.brandl | 2010-10-17 13:06:14 +0200 (So, 17 Okt 2010) | 1 line

  #9237: document sys.call_tracing().
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  r85638 | georg.brandl | 2010-10-17 13:13:37 +0200 (So, 17 Okt 2010) | 1 line

  Port changes to pickle docs apparently lost in py3k.
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  r85639 | georg.brandl | 2010-10-17 13:23:56 +0200 (So, 17 Okt 2010) | 1 line

  Make twisted example a bit more logical.
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  r85641 | georg.brandl | 2010-10-17 13:29:07 +0200 (So, 17 Okt 2010) | 1 line

  Fix documentation of dis.opmap direction.
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  r85642 | georg.brandl | 2010-10-17 13:36:28 +0200 (So, 17 Okt 2010) | 1 line

  #9730: fix example.
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svn+ssh://svn.python.org/python/branches/py3k

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  r85530 | georg.brandl | 2010-10-15 17:32:05 +0200 (Fr, 15 Okt 2010) | 1 line

  Refrain from using inline suites.
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  r85532 | georg.brandl | 2010-10-15 18:03:02 +0200 (Fr, 15 Okt 2010) | 1 line

  #7771: reference to documentation of dictview methods and operations.
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  r85533 | georg.brandl | 2010-10-15 18:07:41 +0200 (Fr, 15 Okt 2010) | 1 line

  #9683: remove broken dead code dealing with nested arguments removed from Py3k, and update the docs and docstrings accordingly.
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  r85534 | georg.brandl | 2010-10-15 18:19:43 +0200 (Fr, 15 Okt 2010) | 1 line

  #9801: document how list and dict proxies created by Managers behave w.r.t. mutable items.
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  r85538 | georg.brandl | 2010-10-15 18:35:46 +0200 (Fr, 15 Okt 2010) | 1 line

  #7303: add documentation for useful pkgutil functions and classes.
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  r85539 | georg.brandl | 2010-10-15 18:42:14 +0200 (Fr, 15 Okt 2010) | 1 line

  Fix issue references.
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  r85540 | georg.brandl | 2010-10-15 18:42:37 +0200 (Fr, 15 Okt 2010) | 1 line

  #6798: fix wrong docs for the arguments to several trace events.
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  r85541 | georg.brandl | 2010-10-15 18:53:24 +0200 (Fr, 15 Okt 2010) | 1 line

  #4968: updates to inspect.is* function docs.
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  r85542 | georg.brandl | 2010-10-15 19:01:15 +0200 (Fr, 15 Okt 2010) | 1 line

  #7790: move table of struct_time members to the actual description of struct_time.
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  r85543 | georg.brandl | 2010-10-15 19:03:02 +0200 (Fr, 15 Okt 2010) | 1 line

  #4785: document strict argument of JSONDecoder, plus add object_pairs_hook in the docstrings.
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  r85546 | georg.brandl | 2010-10-15 19:58:45 +0200 (Fr, 15 Okt 2010) | 1 line

  #5762: fix handling of empty namespace in minidom, which would result in AttributeError on toxml().
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  r85547 | georg.brandl | 2010-10-15 20:00:35 +0200 (Fr, 15 Okt 2010) | 1 line

  #6098: Refrain from claiming DOM level 3 conformance in minidom.
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  r85548 | georg.brandl | 2010-10-15 21:46:19 +0200 (Fr, 15 Okt 2010) | 1 line

  #10072: assume a bit less knowledge of the FTP protocol in the ftplib docs.
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