Ensure that the snippet in doctest_aliases actually contains aliases.

(On Unix) Patch by STINNER Victor.

The rational is the change might cause imcompatiblity problems with
PyYAML. In addition, Raymond wants to kept the different versions of
collections synchronized across Python versions.

PyErr_SetFromErrnoWithUnicodeFilename.

(with the right revisions this time, hopefully)

Fixes #6258.

Merged revisions 72523,72950-72951,72994,73003,73033,73036-73040,73091-73093,73096,73179-73181,73192,73231,73244,73255-73256,73365 via svnmerge from
svn+ssh://pythondev@svn.python.org/sandbox/trunk/2to3/lib2to3

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  r72523 | benjamin.peterson | 2009-05-09 14:42:26 -0500 (Sat, 09 May 2009) | 1 line

  remove parenthesis
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  r72950 | benjamin.peterson | 2009-05-26 18:19:45 -0500 (Tue, 26 May 2009) | 1 line

  remove unused imports
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  r72951 | benjamin.peterson | 2009-05-26 18:27:00 -0500 (Tue, 26 May 2009) | 1 line

  this is no longer executable
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  r72994 | benjamin.peterson | 2009-05-28 15:32:54 -0500 (Thu, 28 May 2009) | 1 line

  fix test_all_fixers on Windows #6134
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  r73003 | benjamin.peterson | 2009-05-28 21:57:28 -0500 (Thu, 28 May 2009) | 4 lines

  make 2to3 test utilities easier to use with other applications (3to2)

  Patch by Joe Amenta
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  r73033 | benjamin.peterson | 2009-05-29 16:58:32 -0500 (Fri, 29 May 2009) | 1 line

  update grammar for multi with statement
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  r73036 | benjamin.peterson | 2009-05-29 17:33:20 -0500 (Fri, 29 May 2009) | 1 line

  simplify fix_unicode
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  r73037 | benjamin.peterson | 2009-05-29 17:53:03 -0500 (Fri, 29 May 2009) | 1 line

  add custom error for pattern syntax errors
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  r73038 | benjamin.peterson | 2009-05-29 17:55:00 -0500 (Fri, 29 May 2009) | 1 line

  complain if details are attached to a token
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  r73039 | benjamin.peterson | 2009-05-29 18:00:28 -0500 (Fri, 29 May 2009) | 1 line

  add a test for whitespace
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  r73040 | benjamin.peterson | 2009-05-29 18:01:17 -0500 (Fri, 29 May 2009) | 1 line

  a fix for emacs highlighting
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  r73091 | benjamin.peterson | 2009-05-31 20:55:25 -0500 (Sun, 31 May 2009) | 1 line

  deprecate set_prefix() and get_prefix() in favor of a prefix property
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  r73092 | benjamin.peterson | 2009-05-31 21:00:51 -0500 (Sun, 31 May 2009) | 1 line

  change hideous java naming scheme
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  r73093 | benjamin.peterson | 2009-05-31 21:01:39 -0500 (Sun, 31 May 2009) | 1 line

  remove dated comment
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  r73096 | benjamin.peterson | 2009-05-31 21:40:53 -0500 (Sun, 31 May 2009) | 1 line

  group tests
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  r73179 | benjamin.peterson | 2009-06-03 13:09:53 -0500 (Wed, 03 Jun 2009) | 1 line

  handle the case where there's multiple trailers #6185
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  r73180 | benjamin.peterson | 2009-06-03 13:18:05 -0500 (Wed, 03 Jun 2009) | 1 line

  scrap __main__ section
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  r73181 | benjamin.peterson | 2009-06-03 13:24:48 -0500 (Wed, 03 Jun 2009) | 1 line

  remove shebang lines and __main__ sections
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  r73192 | benjamin.peterson | 2009-06-03 19:16:30 -0500 (Wed, 03 Jun 2009) | 4 lines

  actually test something here

  Thanks to Joe Amenta for noticing.y
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  r73231 | benjamin.peterson | 2009-06-04 13:38:50 -0500 (Thu, 04 Jun 2009) | 1 line

  remove unused variable
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  r73244 | benjamin.peterson | 2009-06-05 08:39:25 -0500 (Fri, 05 Jun 2009) | 1 line

  allow fixers to give different options in setUp
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  r73255 | benjamin.peterson | 2009-06-06 11:23:46 -0500 (Sat, 06 Jun 2009) | 1 line

  fix the except fixer on one line suites #6222
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  r73256 | benjamin.peterson | 2009-06-06 11:27:40 -0500 (Sat, 06 Jun 2009) | 1 line

  test one-line else and finally clauses
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  r73365 | benjamin.peterson | 2009-06-11 17:01:32 -0500 (Thu, 11 Jun 2009) | 1 line

  normalize whitespace
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