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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_last_weeks(number_of_weeks):
 """Get the last weeks."""

    time_now = datetime.now()
    year = time_now.isocalendar()[0]
    week = time_now.isocalendar()[1]
    weeks = []
    for i in range(0, number_of_weeks):
        start = get_week_dates(year, week - i, as_timestamp=True)[0]
        n_year, n_week = get_year_week(start)
        weeks.append((n_year, n_week))

    return weeks