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comparison CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/lib/python3.8/site-packages/pytz/reference.py @ 69:33d812a61356

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planemo upload commit 2e9511a184a1ca667c7be0c6321a36dc4e3d116d
author jpayne
date Tue, 18 Mar 2025 17:55:14 -0400
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67:0e9998148a16 69:33d812a61356
1 '''
2 Reference tzinfo implementations from the Python docs.
3 Used for testing against as they are only correct for the years
4 1987 to 2006. Do not use these for real code.
5 '''
6
7 from datetime import tzinfo, timedelta, datetime
8 from pytz import HOUR, ZERO, UTC
9
10 __all__ = [
11 'FixedOffset',
12 'LocalTimezone',
13 'USTimeZone',
14 'Eastern',
15 'Central',
16 'Mountain',
17 'Pacific',
18 'UTC'
19 ]
20
21
22 # A class building tzinfo objects for fixed-offset time zones.
23 # Note that FixedOffset(0, "UTC") is a different way to build a
24 # UTC tzinfo object.
25 class FixedOffset(tzinfo):
26 """Fixed offset in minutes east from UTC."""
27
28 def __init__(self, offset, name):
29 self.__offset = timedelta(minutes=offset)
30 self.__name = name
31
32 def utcoffset(self, dt):
33 return self.__offset
34
35 def tzname(self, dt):
36 return self.__name
37
38 def dst(self, dt):
39 return ZERO
40
41
42 import time as _time
43
44 STDOFFSET = timedelta(seconds=-_time.timezone)
45 if _time.daylight:
46 DSTOFFSET = timedelta(seconds=-_time.altzone)
47 else:
48 DSTOFFSET = STDOFFSET
49
50 DSTDIFF = DSTOFFSET - STDOFFSET
51
52
53 # A class capturing the platform's idea of local time.
54 class LocalTimezone(tzinfo):
55
56 def utcoffset(self, dt):
57 if self._isdst(dt):
58 return DSTOFFSET
59 else:
60 return STDOFFSET
61
62 def dst(self, dt):
63 if self._isdst(dt):
64 return DSTDIFF
65 else:
66 return ZERO
67
68 def tzname(self, dt):
69 return _time.tzname[self._isdst(dt)]
70
71 def _isdst(self, dt):
72 tt = (dt.year, dt.month, dt.day,
73 dt.hour, dt.minute, dt.second,
74 dt.weekday(), 0, -1)
75 stamp = _time.mktime(tt)
76 tt = _time.localtime(stamp)
77 return tt.tm_isdst > 0
78
79 Local = LocalTimezone()
80
81
82 def first_sunday_on_or_after(dt):
83 days_to_go = 6 - dt.weekday()
84 if days_to_go:
85 dt += timedelta(days_to_go)
86 return dt
87
88
89 # In the US, DST starts at 2am (standard time) on the first Sunday in April.
90 DSTSTART = datetime(1, 4, 1, 2)
91 # and ends at 2am (DST time; 1am standard time) on the last Sunday of Oct.
92 # which is the first Sunday on or after Oct 25.
93 DSTEND = datetime(1, 10, 25, 1)
94
95
96 # A complete implementation of current DST rules for major US time zones.
97 class USTimeZone(tzinfo):
98
99 def __init__(self, hours, reprname, stdname, dstname):
100 self.stdoffset = timedelta(hours=hours)
101 self.reprname = reprname
102 self.stdname = stdname
103 self.dstname = dstname
104
105 def __repr__(self):
106 return self.reprname
107
108 def tzname(self, dt):
109 if self.dst(dt):
110 return self.dstname
111 else:
112 return self.stdname
113
114 def utcoffset(self, dt):
115 return self.stdoffset + self.dst(dt)
116
117 def dst(self, dt):
118 if dt is None or dt.tzinfo is None:
119 # An exception may be sensible here, in one or both cases.
120 # It depends on how you want to treat them. The default
121 # fromutc() implementation (called by the default astimezone()
122 # implementation) passes a datetime with dt.tzinfo is self.
123 return ZERO
124 assert dt.tzinfo is self
125
126 # Find first Sunday in April & the last in October.
127 start = first_sunday_on_or_after(DSTSTART.replace(year=dt.year))
128 end = first_sunday_on_or_after(DSTEND.replace(year=dt.year))
129
130 # Can't compare naive to aware objects, so strip the timezone from
131 # dt first.
132 if start <= dt.replace(tzinfo=None) < end:
133 return HOUR
134 else:
135 return ZERO
136
137 Eastern = USTimeZone(-5, "Eastern", "EST", "EDT")
138 Central = USTimeZone(-6, "Central", "CST", "CDT")
139 Mountain = USTimeZone(-7, "Mountain", "MST", "MDT")
140 Pacific = USTimeZone(-8, "Pacific", "PST", "PDT")