how to use the differenceincalendarisoweekyears function from date-fns in javascript

To use the differenceInCalendarISOWeekYears function from date-fns in JavaScript, you will need to install the date-fns library:

npm install date-fns
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Then, you can import the function into your JavaScript file and use it as follows:

index.tsx
import { differenceInCalendarISOWeekYears } from 'date-fns';

const result = differenceInCalendarISOWeekYears(
  new Date(2021, 0, 1), 
  new Date(2024, 0, 1)
);

console.log(result);
// Output: 2
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In this example, we are using the differenceInCalendarISOWeekYears function to calculate the difference in ISO week years between January 1st, 2021 and January 1st, 2024. The result should be 2 since these two dates are in different ISO week years.