为什么这样会报错？求解

Question

```javascript
<template>
    <swiper>
                //下面这行代码会显示红色波浪线，这是为什么？
            <swiper-item v-for="item in banners">
                <a :href="item.link">
                    <img :src="item.image" alt="">
                </a>
            </swiper-item> 
               
    </swiper>
</template>

<script>
import {Swiper, SwiperItem} from '@/components/common/swiper'


export default {
    name: "HomeSwiper",
    props: {
        banners: {
            type: Array,
            default() {
                return []
            }
        }
    },
    components: {
        Swiper,
        SwiperItem
    }
}
</script>

<style scoped>

</style>>
    
</style>

```

Answer 1

swiper-item v-for后面加个key