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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 find_all_models(models):
 """ Yield all models and their parents. """

    for model in models:
        yield model
        # noinspection PyProtectedMember
        for parent in model._meta.parents.keys():
            for parent_model in find_all_models((parent,)):
                yield parent_model