Add __hash__ to VocabString class.
@@ -85,6 +85,8 @@ class VocabField(fields.TypedField):
class VocabString(PatternFieldGroup, entities.Entity):
+ __hash__ = entities.Entity.__hash__
+
_namespace = 'http://cybox.mitre.org/default_vocabularies-2'
# All subclasses should override this
_XSI_TYPE = None
