Disambiguate the use of the term value in the example.

Author: metaperl

docs/source/using_traitlets.rst

@@ -95,29 +95,30 @@ Basic Example: Validating the Parity of a Trait
     from traitlets import HasTraits, TraitError, Int, Bool, validate
 
     class Parity(HasTraits):
-        value = Int()
+        data = Int()
         parity = Int()
 
-        @validate('value')
-        def _valid_value(self, proposal):
+        @validate('data')
+        def _valid_data(self, proposal):
             if proposal['value'] % 2 != self.parity:
-                raise TraitError('value and parity should be consistent')
+                raise TraitError('data and parity should be consistent')
             return proposal['value']
 
         @validate('parity')
         def _valid_parity(self, proposal):
             parity = proposal['value']
             if parity not in [0, 1]:
                 raise TraitError('parity should be 0 or 1')
-            if self.value % 2 != parity:
-                raise TraitError('value and parity should be consistent')
+            if self.data % 2 != parity:
+                raise TraitError('data and parity should be consistent')
             return proposal['value']
 
-    parity_check = Parity(value=2)
+
+    parity_check = Parity(data=2)
 
     # Changing required parity and value together while holding cross validation
     with parity_check.hold_trait_notifications():
-        parity_check.value = 1
+        parity_check.data = 1
         parity_check.parity = 1
 
 Notice how all of the examples above return