• I have searched the issues of this repository and believe that this is not a duplicate.

What problem does this feature solve?

Now the week num in WeekPicker is the number of year , but for some one that is not clear, they want the number of month.
现在WeekPicker的组件里，周数指的是一年当中的第几周，但对一些客户来说，这个不够明确，他们比较希望的表达是某个月的第几周。

What does the proposed API look like?

I hope there is a method to format the week number, just like this.

<WeekPicker
  weekNumberFormatter = {(beginDate, endDate) => ''}
/>