Issue #14742: test_unparse now only checks a limited number of files unless the 'cpu' resource is specified.

 - parenthesize lambdas, to avoid turning (lambda : int)() into lambda: int()
 - unparse an infinite float literals in the AST as an overflowing finite value

unparse.py now successfully round-trips on all valid Lib/*.py and Lib/test/*.py files.

 - relative imports
 - keyword-only arguments
 - function annotations
 - class decorators
 - raise ... from ...
 - except ... as ...
 - nonlocal
 - bytes literals
 - set literals
 - set comprehensions
 - dict comprehensions
Removals:
 - print statement.

Some of this should be backported to 2.x.

svn+ssh://pythondev@svn.python.org/python/trunk

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  r82345 | mark.dickinson | 2010-06-28 20:54:19 +0100 (Mon, 28 Jun 2010) | 1 line

  unparse.py:  fix mispaced parentheses in chained comparisons
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svn+ssh://pythondev@svn.python.org/python/trunk

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  r82338 | mark.dickinson | 2010-06-28 20:31:41 +0100 (Mon, 28 Jun 2010) | 9 lines

  Fix some shallow bugs in Demo/parser/unparse.py, and add tests:

    - insert commas between entries in del statement
    - left and right shifts were represented as >> and << (respectively); reverse
    - unindent properly after for: else:  or while: else:
    - add parens around the result of an unary operation
    - add parens around negative numbers, to avoid turning (-1)**2 into -1**2.
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  r82340 | mark.dickinson | 2010-06-28 20:34:15 +0100 (Mon, 28 Jun 2010) | 1 line

  Fix typo in test_unparse.py.
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  r82341 | mark.dickinson | 2010-06-28 20:38:19 +0100 (Mon, 28 Jun 2010) | 1 line

  Set svn:eol-style on test_unparse.py.
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  - insert commas between entries in del statement
  - left and right shifts were represented as >> and << (respectively); reverse
  - unindent properly after for: else:  or while: else:
  - add parens around the result of an unary operation
  - add parens around negative numbers, to avoid turning (-1)**2 into -1**2.