code: def get_external_method(class_object, method_name, *args, **kwargs):
      
      related_model = get_external_model(class_object)
      if related_model is not None:
          f = getattr(related_model, method_name, None)
          if f:
              instance = related_model()
              return f(instance, *args, **kwargs)
          else:
              return None
      return None
docs: Given a class (class_object), a name for a method (method_name) and its arguments,
      it searchs for the method in the related model (throught the codenerix abstract class) and
      it executes that method or return None if no method is found.