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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _assert_correct_model(model_to_check, model_reference, obj_name):
 """ Helper that asserts the model_to_check is the model_reference or one of its subclasses. If not, raise an ImplementationError, using "obj_name" to describe the name of the argument. """

        if not issubclass(model_to_check, model_reference):
            raise ConfigurationException('The %s model must be a subclass of %s'
                                         % (obj_name, model_reference.__name__))