FlatList keyExtractor

import React from 'react';
import { FlatList, Text } from 'react-native';

export default function Nums() {
  const data = [{ id: 1 }, { id: 2 }];
  return (
    <FlatList
      data={data}
      keyExtractor={(item) => item.id}
      renderItem={({ item }) => <Text>{item.id}</Text>}
    />
  );
}