Add __future__ import for print_function.  It's a no-op in 3.0, but it needs to not be a syntax error.
Closes issue 2436.
diff --git a/Include/code.h b/Include/code.h
index 56d6cb5..e576bbb 100644
--- a/Include/code.h
+++ b/Include/code.h
@@ -48,6 +48,7 @@
 #define CO_FUTURE_DIVISION    	0x2000
 #define CO_FUTURE_ABSOLUTE_IMPORT 0x4000 /* do absolute imports by default */
 #define CO_FUTURE_WITH_STATEMENT  0x8000
+#define CO_FUTURE_PRINT_FUNCTION  0x10000
 #endif
 
 /* This should be defined if a future statement modifies the syntax.