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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 views(model: "Model") -> list: """Return a model's views keyed on what events they respond to. Model views are added by calling :func:`view` on a model. """

    if not isinstance(model, Model):
        raise TypeError("Expected a Model, not %r." % model)
    return model._model_views[:]