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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 register_plugin(cls, model, plugin):
        '''
        Reguster a plugin for the model.

        The only one plugin can be registered. If you want to combine plugins, use CompoundPlugin.
        '''
        logger.info("Plugin registered for %s: %s", model, plugin)
        cls.plugins[model] = plugin