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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 is_model_registered(app_label, model_name):
 """ Checks whether the given model is registered or not. It is usefull to prevent Machina models for being registered if they are overridden by local apps. """

    try:
        apps.get_registered_model(app_label, model_name)
    except LookupError:
        return False
    else:
        return True