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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 compare(self, compare_recipe, suffix='_compare'):
 """Adds a comparison recipe to a base recipe."""

        assert isinstance(compare_recipe, Recipe)
        assert isinstance(suffix, basestring)
        self.compare_recipe.append(compare_recipe)
        self.suffix.append(suffix)
        self.dirty = True
        return self.recipe