Could not identify existing codebase is options api or composition api - vue.js

Question

I am new to vue js, i was from angular...
From what i read, vue js has two way of writing, options API vs composition API.
Options API has something like:
<script lang="ts">
import { defineComponent } from "vue";
export default defineComponent({
name: "App",
data() {
return {
count: 0
};
}
});
</script>
Where Composition API has the format of:
<script lang="ts">
import { ref, defineComponent } from "vue";
export default defineComponent({
name: "App",
setup: () => {
const count = ref(0);
return { count };
},
});
</script>
But when i read the existing code base, i can't really know which type of codebase is this? What is the difference?
We use micro frontend as we are small part of entire webpage.
<script lang="ts">
import { Component, Vue } from 'XXXXX';
import { BannerType, showBanner } XXXXX';
import { itemService} from 'XXXXX';
#Component
export default class UploadItemModal extends Vue {
#Ref('form')
readonly form!: InstanceType<typeof ValidationObserver>;
private isUploading = false;
private showUploadError = '';
private showProgressbar = false;
uploadFieldName = '';
fileCount = 0;
fileSize = '';
selectedFile: File = new File([], '');
uploading = {
loaded: 0,
total: 1,
};
private closeDialog(): void {
//implementation hidden
}
private clearData(): void {
//implementation hidden
}
</script>