3 examples of 'python datetime add month' in Python

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def AddMonths(start_date, months):
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  """A simple convenience utility for adding months to a given start date.
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  This increments the months by adding the number of days in the current month
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  to the current month, for each month.
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  Args:
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    start_date: date The date months are being added to.
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    months: int The number of months to add.
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  Returns:
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    A date equal to the start date incremented by the given number of months.
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  """
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  current_date = start_date
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  i = 0
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  while i < months:
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    month_days = calendar.monthrange(current_date.year, current_date.month)[1]
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    current_date += timedelta(days=month_days)
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    i += 1
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  return current_date

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def add_month_based_on_weekday(date):
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    # Is the weekday of this date the last one?
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    is_last_weekday = (date + datetime.timedelta(weeks=1)).month != date.month
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    # Some magic which pushes and pulls some weeks until
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    # it fits right.
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    new_date = date + datetime.timedelta(weeks=4)
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    if (new_date.day + 6) // 7 < (date.day + 6) // 7:
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        new_date += datetime.timedelta(weeks=1)
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    next_month = add_month(date, override_day=1)
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    if new_date.month == (next_month.month - 1 if next_month.month > 1 else 12):
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        new_date += datetime.timedelta(weeks=1)
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    elif new_date.month == (next_month.month + 1 if next_month.month < 12 else 1):
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        new_date += datetime.timedelta(weeks=-1)
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    # If the weekdate of the original date was the last one,
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    # and there is some room left, add a week extra so this
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    # will result in a last weekday of the month again.
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    if is_last_weekday and (new_date + datetime.timedelta(weeks=1)).month == new_date.month:
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        new_date += datetime.timedelta(weeks=1)
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    return new_date

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def test_add_month_with_overflow():
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    assert pendulum.datetime(2012, 1, 31).add(months=1).month == 2