Fixed #9200 -- Added new form wizard to formtools based on class based views. Many thanks to Stephan Jäkel, ddurham and ElliottM for their work.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16307 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/utils/functional.py

@@ -265,3 +265,24 @@ class SimpleLazyObject(LazyObject):
 
     def _setup(self):
         self._wrapped = self._setupfunc()
+
+
+class lazy_property(property):
+    """
+    A property that works with subclasses by wrapping the decorated
+    functions of the base class.
+    """
+    def __new__(cls, fget=None, fset=None, fdel=None, doc=None):
+        if fget is not None:
+            @wraps(fget)
+            def fget(instance, instance_type=None, name=fget.__name__):
+                return getattr(instance, name)()
+        if fset is not None:
+            @wraps(fset)
+            def fset(instance, value, name=fset.__name__):
+                return getattr(instance, name)(value)
+        if fdel is not None:
+            @wraps(fdel)
+            def fdel(instance, name=fdel.__name__):
+                return getattr(instance, name)()
+        return property(fget, fset, fdel, doc)