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Change from double quotes to single quotes.

Co-authored-by: Tomas R. <tomas.roun8@gmail.com>

Author: ravg998

Lib/test/test_pathlib/test_read.py

@@ -331,8 +331,8 @@ def test_info_is_symlink(self):
 
     def test_invalid_mode(self): 
         p = self.root / 'fileA'
-        with self.assertRaisesRegex(ValueError, "invalid mode"): 
-            vfsopen(p, "q")
+        with self.assertRaisesRegex(ValueError, 'invalid mode'): 
+            vfsopen(p, 'q')
 
 
 class ZipPathReadTest(ReadTestBase, unittest.TestCase):