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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 unregister(self, recipe):
 """ Unregisters an existing recipe, so that this recipe is no longer available. This function is mainly used during plugin deactivation. :param recipe: Name of the recipe """

        if recipe not in self.recipes.keys():
            self.__log.warning("Can not unregister recipe %s" % recipe)
        else:
            del (self.recipes[recipe])
            self.__log.debug("Recipe %s got unregistered" % recipe)