Given an array of dates, return each shifted 10 business days earlier. If a date itself falls on a weekend, first roll it backward to the nearest preceding business day before counting the 10 business days back.
Input
array(['2019-02-20', '2019-06-20', '2090-03-23'], dtype='datetime64[D]')
Output
array(['2019-02-06', '2019-06-06', '2090-03-09'], dtype='datetime64[D]')