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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_point_model(cls):
 """ Returns plugin point model instance. Only used from plugin classes. """

        if is_plugin_point(cls):
            raise Exception(_('This method is only available to plugin '
                              'classes.'))
        else:
            return PluginPointModel.objects.\
                get(plugin__pythonpath=cls.get_pythonpath())