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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(self, recipe):
 """ Registers a new recipe class. """


        if not isinstance(recipe, (list, tuple)):
            recipe = [recipe, ]

        for item in recipe:
            recipe = self.get_recipe_instance_from_class(item)
            self._registry[recipe.slug] = recipe