[Python] Python: How to use changing window in pandas rolling groupby function

I have a DataFrame with monthly data that looks something like this:

id date window_in_months value
1 2000-01-01 3 20
1 2000-02-01 3 30
2 2000-01-01 12 40
2 2000-02-01 12 60

I want to do a rolling groupby but use the value in column window_in_months as the window parameter. I can use a static window by just doing:

df.groupby('id')['value'].rolling(window=3, min_periods=3)

But I can't figure out how to have the window and min_periods change with the group under consideration. The window_in_months will always be the same for all ids that are the same.

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