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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 get_content_models(cls):
 """ Return all subclasses of the concrete model. """

        concrete_model = base_concrete_model(ContentTyped, cls)
        return [m for m in apps.get_models()
                if m is not concrete_model and issubclass(m, concrete_model)]