Issue #4445: save 3 bytes (on average, on a typical machine) per
string allocation.
diff --git a/Lib/test/test_sys.py b/Lib/test/test_sys.py
index 35467e4..8e10ec6 100644
--- a/Lib/test/test_sys.py
+++ b/Lib/test/test_sys.py
@@ -631,8 +631,8 @@
         # slice
         check(slice(1), size(h + '3P'))
         # str
-        check('', size(vh + 'lic'))
-        check('abc', size(vh + 'lic') + 3*self.c)
+        check('', struct.calcsize(vh + 'li') + 1)
+        check('abc', struct.calcsize(vh + 'li') + 1 + 3*self.c)
         # super
         check(super(int), size(h + '3P'))
         # tuple