Fixed test_tempfilepager in test_pydoc on Windows.

Filename such as r'c:\users\db3l\appdata\local\temp\tmph3vkvf' contains '\t'
which is interpreted by ast.literal_eval() as a tabulation.

Lib/test/test_pydoc.py

@@ -473,8 +473,9 @@ class TestUnicode(unittest.TestCase):
 
         output = {}
         def mock_system(cmd):
-            import ast
-            output['content'] = open(ast.literal_eval(cmd.strip())).read()
+            filename = cmd.strip()[1:-1]
+            self.assertEqual('"' + filename + '"', cmd.strip())
+            output['content'] = open(filename).read()
         saved, os.system = os.system, mock_system
         try:
             pydoc.tempfilepager(doc, '')