fix isprintable() on space characters #5126
diff --git a/Lib/test/test_unicode.py b/Lib/test/test_unicode.py
index b40ee84..1fddc06 100644
--- a/Lib/test/test_unicode.py
+++ b/Lib/test/test_unicode.py
@@ -424,6 +424,7 @@
 
     def test_isprintable(self):
         self.assertTrue("".isprintable())
+        self.assertTrue(" ".isprintable())
         self.assertTrue("abcdefg".isprintable())
         self.assertFalse("abcdefg\n".isprintable())
         # some defined Unicode character