closest_date.py

import datetime

dates = ['20220902', '20220909', '20220916', '20220923', '20220930',
         '20221007', '20221014', '20221021', '20221118', '20221216',
         '20230120', '20230317', '20230421', '20230616', '20230915',
         '20240119', '20240315', '20240621']
         
# [ datetime.date(2022, 9, 2), datetime.date(2022, 9, 9), datetime.date(2022, 9, 16), ... ]
dates = [datetime.datetime.strptime(d, '%Y%m%d').date() for d in dates]

pivot = datetime.date.today() + datetime.timedelta(days=16)

closest_date = min(dates, key=lambda item: abs(item-pivot))

print(
    closest_date.strftime('%Y%m%d')
)
# '20220916'