grandfatherson/filters.py
def start(cls, now, number, **options):
        """
        Return the starting datetime: ``number`` of months before ``now``.
        """
        year = now.year
        month = now.month - number + 1
        # Handle negative months
        if month < 0:
            year = year + (month // cls.MONTHS_IN_YEAR)
            month = month % cls.MONTHS_IN_YEAR
        # Handle December
        if month == 0:
            year = year - 1
            month = 12
        return cls.mask(now, **options).replace(year=year, month=month)
def start(cls, now, number, **options):
        """
        Return the starting datetime: ``number`` of months before ``now``.
        """
        year = now.year
        month = now.month - number + 1
        # Handle negative months
        if month < 0:
            year = year + (month // cls.MONTHS_IN_YEAR)
            month = month % cls.MONTHS_IN_YEAR
        # Handle December
        if month == 0:
            year = year - 1
            month = 12
        return cls.mask(now, **options).replace(year=year, month=month)
Return the starting datetime: ``number`` of months before ``now``.