如何使用带有sum类型的elm-monocle？

"elm-community/elm-monocle": "x.x.x"

import Monocle.Prism exposing (Prism)
import Monocle.Optional exposing (Optional)
import Monocle.Sum exposing (Sum)
import Monocle.Traversal exposing (Traversal)

type Fruit
    = Apple Int
    | Banana String
    | Orange

-- 定义一个Prism，用于访问Apple构造器中的整数
applePrism : Prism Fruit Int
applePrism =
    Prism (\fruit -> case fruit of
        Apple n -> Just n
        _ -> Nothing)
        Apple

-- 定义一个Optional，用于访问Banana构造器中的字符串
bananaOptional : Optional Fruit String
bananaOptional =
    Optional (\fruit -> case fruit of
        Banana s -> Just s
        _ -> Nothing)
        (\s -> Banana s)

-- 定义一个Traversal，用于访问所有构造器中的字符串
fruitTraversal : Traversal Fruit String
fruitTraversal =
    Traversal (\update fruit -> case fruit of
        Apple n -> Apple n
        Banana s -> update (Banana s)
        Orange -> Orange)

-- 使用Prism获取Apple构造器中的整数
getApple : Fruit -> Maybe Int
getApple fruit =
    Monocle.Prism.get applePrism fruit

-- 使用Optional获取Banana构造器中的字符串
getBanana : Fruit -> Maybe String
getBanana fruit =
    Monocle.Optional.get bananaOptional fruit

-- 使用Traversal将所有构造器中的字符串转换为大写
toUpper : Fruit -> Fruit
toUpper fruit =
    Monocle.Traversal.over fruitTraversal String.toUpper fruit