diff --git a/wxPython/src/_core_ex.py b/wxPython/src/_core_ex.py
index fdfe05f5b6..0bb3c2e8b4 100644
--- a/wxPython/src/_core_ex.py
+++ b/wxPython/src/_core_ex.py
@@ -6,6 +6,8 @@ try:
 except NameError:
     __builtins__.True = 1==1
     __builtins__.False = 1==0
+    def bool(value): return not not value
+    __builtins__.bool = bool