| 5585 | DSTEND = datetime(1, 10, 25, 1) |
| 5586 | |
| 5587 | class USTimeZone(tzinfo): |
| 5588 | |
| 5589 | def __init__(self, hours, reprname, stdname, dstname): |
| 5590 | self.stdoffset = timedelta(hours=hours) |
| 5591 | self.reprname = reprname |
| 5592 | self.stdname = stdname |
| 5593 | self.dstname = dstname |
| 5594 | |
| 5595 | def __repr__(self): |
| 5596 | return self.reprname |
| 5597 | |
| 5598 | def tzname(self, dt): |
| 5599 | if self.dst(dt): |
| 5600 | return self.dstname |
| 5601 | else: |
| 5602 | return self.stdname |
| 5603 | |
| 5604 | def utcoffset(self, dt): |
| 5605 | return self.stdoffset + self.dst(dt) |
| 5606 | |
| 5607 | def dst(self, dt): |
| 5608 | if dt is None or dt.tzinfo is None: |
| 5609 | # An exception instead may be sensible here, in one or more of |
| 5610 | # the cases. |
| 5611 | return ZERO |
| 5612 | assert dt.tzinfo is self |
| 5613 | |
| 5614 | # Find first Sunday in April. |
| 5615 | start = first_sunday_on_or_after(DSTSTART.replace(year=dt.year)) |
| 5616 | assert start.weekday() == 6 and start.month == 4 and start.day <= 7 |
| 5617 | |
| 5618 | # Find last Sunday in October. |
| 5619 | end = first_sunday_on_or_after(DSTEND.replace(year=dt.year)) |
| 5620 | assert end.weekday() == 6 and end.month == 10 and end.day >= 25 |
| 5621 | |
| 5622 | # Can't compare naive to aware objects, so strip the timezone from |
| 5623 | # dt first. |
| 5624 | if start <= dt.replace(tzinfo=None) < end: |
| 5625 | return HOUR |
| 5626 | else: |
| 5627 | return ZERO |
| 5628 | |
| 5629 | Eastern = USTimeZone(-5, "Eastern", "EST", "EDT") |
| 5630 | Central = USTimeZone(-6, "Central", "CST", "CDT") |