Check out example codes for "less than date query sqlachemy". It will help you in understanding the concepts better.

Code Example 1

current_time = datetime.datetime.utcnow()

ten_weeks_ago = current_time - datetime.timedelta(weeks=10)

subjects_within_the_last_ten_weeks = session.query(Subject).filter(
    Subject.time > ten_weeks_ago).all()

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