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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 calculate_leapdays(init_date, final_date):
 """Currently unsupported, it only works for differences in years."""


    leap_days = (final_date.year - 1) // 4 - (init_date.year - 1) // 4
    leap_days -= (final_date.year - 1) // 100 - (init_date.year - 1) // 100
    leap_days += (final_date.year - 1) // 400 - (init_date.year - 1) // 400

    # TODO: Internal date correction (e.g. init_date is 1-March or later)

    return datetime.timedelta(days=leap_days)