turned default_value() of ItemField into a property

--HG--
extra : convert_revision : svn%3Ab85faa78-f9eb-468e-a121-7cced6da292c%40878

scrapy/trunk/scrapy/contrib_exp/newitem/fields.py

@@ -10,7 +10,7 @@ class ItemFieldValueError(Exception):
 class ItemField(object):
     def __init__(self, required=False, default=None):
         self.required = required
-        self.default = default
+        self._default = default
 
     def assign(self, value):
         if hasattr(value, '__iter__'):
@@ -29,9 +29,10 @@ class ItemField(object):
         "Converts the input iterable into a single value."
         return ' '.join(value)
 
-    def default_value(self):
+    @property
+    def default(self):
         "Returns the default value for this field"
-        return self.default or self.to_python(None)
+        return self._default or self.to_python(None)
 
 
 class BooleanItemField(ItemField):

scrapy/trunk/scrapy/contrib_exp/newitem/models.py

@@ -28,7 +28,7 @@ class Item(object):
             try:
                 return self._values[name]
             except KeyError:
-                return self._fields[name].default_value()
+                return self._fields[name].default
         else:
             return object.__getattribute__(self, name)