fix meta invalid escape in test_invalid_escape_locations_with_offset

Author: graingert

Lib/test/test_string_literals.py

@@ -177,7 +177,7 @@ def test_eval_str_invalid_octal_escape(self):
     def test_invalid_escape_locations_with_offset(self):
         with warnings.catch_warnings(record=True) as w:
             warnings.simplefilter('always', category=SyntaxWarning)
-            eval("\"'''''''''''''''''''''invalid\ Escape\"")
+            eval("\"'''''''''''''''''''''invalid\\ Escape\"")
         self.assertEqual(len(w), 1)
         self.assertEqual(str(w[0].message),
                          r'"\ " is an invalid escape sequence. Such sequences '