All super methods on extension method override

SwiftMetaModelGenerator/templates/meta_model.stencil

@@ -27,7 +27,11 @@ extension {{class.name}}
         {% endif %}
         {% endfor %}
         default:
-            fatalError("Cannot set value for key \(key)")
+            {% if class.needsMethodOverride %}
+                    super.setValueByKey(key: key, value: value)
+            {% else %}
+                print("Cannot find variable \(key)")
+            {% endif %}
         }
     }
     
@@ -41,7 +45,11 @@ extension {{class.name}}
         {% endif %}
         {% endfor %}
         default:
-            fatalError("Cannot set value for key \(key)")
+            {% if class.needsMethodOverride %}
+                return super.getValueByKey(key: key)
+            {% else %}
+                return nil
+            {% endif %}
         }
     }
 }