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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 _enforce_instance(model_or_class):
 """ It's a common mistake to not initialize a schematics class. We should handle that by just calling the default constructor. """

    if isinstance(model_or_class, type) and issubclass(model_or_class, BaseType):
        return model_or_class()
    return model_or_class