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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_child_models(self):
 """ Get child models from registered plugins. Fallback to the child model admin and its base model if no plugins are registered. """

        child_models = []
        for plugin in self.child_model_plugin_class.get_plugins():
            child_models.append((plugin.model, plugin.model_admin))
        if not child_models:
            child_models.append((
                self.child_model_admin.base_model,
                self.child_model_admin,
            ))
        return child_models