Ensure that code object names (co_name) are unicode.
Verify that they print properly too.
diff --git a/Python/compile.c b/Python/compile.c
index 8ae4036..d2bfe86 100644
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -2991,7 +2991,7 @@
 {
 	static identifier name;
 	if (!name) {
-		name = PyString_FromString("<dictcomp>");
+		name = PyUnicode_FromString("<dictcomp>");
 		if (!name)
 			return 0;
 	}