How to omit 'defineComponent' in vue3

<script setup lang="ts">
import { reactive,  PropType } from 'vue'

defineProps({
    msg: {
        type: Object as PropType<string>,
        required: false,
        default: "hi"
    }
})

/*
defineProps<{
    msg: {
        type: string,
        required: false,
        default: "hi",
    }
}>()
*/

const dict = reactive({
})
</script>

Did you see the setup keyword out there? That’s the key. 

https://v3.vuejs.org/api/sfc-script-setup.html#basic-syntax

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