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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 set_content_model(self):
 """ Set content_model to the child class's related name, or None if this is the base class. """

        if not self.content_model:
            is_base_class = (
                base_concrete_model(ContentTyped, self) == self.__class__)
            self.content_model = (
                None if is_base_class else self.get_content_model_name())