[lib] CLUnfolder: Fix getter that return nothing

library/cadbiom/models/clause_constraints/mcl/CLUnfolder.py

@@ -469,7 +469,7 @@ class CLUnfolder(object):
     @property
     def final_constraints(self):
         """For tests: returns coded final constraints"""
-        self.__final_constraints
+        return self.__final_constraints
 
     ## Variables management ####################################################
     def var_names_in_clause(self, clause):