Remove thirdparty/unittest2 from webkitpy and require python2.7.

Tools/Scripts/webkitpy/common/checkout/diff_parser_unittest.py

 # Copyright (C) 2009 Google Inc. All rights reserved.
 #
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 # modification, are permitted provided that the following conditions are
 # met:
 #
 #    * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #    * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
 # in the documentation and/or other materials provided with the
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 #    * Neither the name of Google Inc. nor the names of its
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 # this software 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
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 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 import cStringIO as StringIO
-import webkitpy.thirdparty.unittest2 as unittest
 import diff_parser
 import re
+import unittest
 
 from webkitpy.common.checkout.diff_test_data import DIFF_TEST_DATA
 
 class DiffParserTest(unittest.TestCase):
     maxDiff = None
 
     def test_diff_parser(self, parser = None):
         if not parser:
             parser = diff_parser.DiffParser(DIFF_TEST_DATA.splitlines())
         self.assertEqual(3, len(parser.files))
@@ skipping 123 matching lines @@
  A
  B
  C
 +D
  E
  F
 """)
 
         self.assertMultiLineEqual(output, ''.join(diff_parser.git_diff_to_svn_diff(x) for x in shortfmt.readlines()))
         self.assertMultiLineEqual(output, ''.join(diff_parser.git_diff_to_svn_diff(x) for x in inputfmt.readlines()))