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+'''
+datetime.tzinfo timezone definitions generated from the
+Olson timezone database:
+
+ ftp://elsie.nci.nih.gov/pub/tz*.tar.gz
+
+See the datetime section of the Python Library Reference for information
+on how to use these modules.
+'''
+
+# The Olson database is updated several times a year.
+OLSON_VERSION = '2014j'
+VERSION = '2014.10' # Switching to pip compatible version numbering.
+__version__ = VERSION
+
+OLSEN_VERSION = OLSON_VERSION # Old releases had this misspelling
+
+__all__ = [
+ 'timezone', 'utc', 'country_timezones', 'country_names',
+ 'AmbiguousTimeError', 'InvalidTimeError',
+ 'NonExistentTimeError', 'UnknownTimeZoneError',
+ 'all_timezones', 'all_timezones_set',
+ 'common_timezones', 'common_timezones_set',
+ ]
+
+import sys, datetime, os.path, gettext
+
+try:
+ from pkg_resources import resource_stream
+except ImportError:
+ resource_stream = None
+
+from pytz.exceptions import AmbiguousTimeError
+from pytz.exceptions import InvalidTimeError
+from pytz.exceptions import NonExistentTimeError
+from pytz.exceptions import UnknownTimeZoneError
+from pytz.lazy import LazyDict, LazyList, LazySet
+from pytz.tzinfo import unpickler
+from pytz.tzfile import build_tzinfo, _byte_string
+
+
+try:
+ unicode
+
+except NameError: # Python 3.x
+
+ # Python 3.x doesn't have unicode(), making writing code
+ # for Python 2.3 and Python 3.x a pain.
+ unicode = str
+
+ def ascii(s):
+ r"""
+ >>> ascii('Hello')
+ 'Hello'
+ >>> ascii('\N{TRADE MARK SIGN}') #doctest: +IGNORE_EXCEPTION_DETAIL
+ Traceback (most recent call last):
+ ...
+ UnicodeEncodeError: ...
+ """
+ s.encode('US-ASCII') # Raise an exception if not ASCII
+ return s # But return the original string - not a byte string.
+
+else: # Python 2.x
+
+ def ascii(s):
+ r"""
+ >>> ascii('Hello')
+ 'Hello'
+ >>> ascii(u'Hello')
+ 'Hello'
+ >>> ascii(u'\N{TRADE MARK SIGN}') #doctest: +IGNORE_EXCEPTION_DETAIL
+ Traceback (most recent call last):
+ ...
+ UnicodeEncodeError: ...
+ """
+ return s.encode('US-ASCII')
+
+
+def open_resource(name):
+ """Open a resource from the zoneinfo subdir for reading.
+
+ Uses the pkg_resources module if available and no standard file
+ found at the calculated location.
+ """
+ name_parts = name.lstrip('/').split('/')
+ for part in name_parts:
+ if part == os.path.pardir or os.path.sep in part:
+ raise ValueError('Bad path segment: %r' % part)
+ filename = os.path.join(os.path.dirname(__file__),
+ 'zoneinfo', *name_parts)
+ if not os.path.exists(filename) and resource_stream is not None:
+ # http://bugs.launchpad.net/bugs/383171 - we avoid using this
+ # unless absolutely necessary to help when a broken version of
+ # pkg_resources is installed.
+ return resource_stream(__name__, 'zoneinfo/' + name)
+ return open(filename, 'rb')
+
+
+def resource_exists(name):
+ """Return true if the given resource exists"""
+ try:
+ open_resource(name).close()
+ return True
+ except IOError:
+ return False
+
+
+# Enable this when we get some translations?
+# We want an i18n API that is useful to programs using Python's gettext
+# module, as well as the Zope3 i18n package. Perhaps we should just provide
+# the POT file and translations, and leave it up to callers to make use
+# of them.
+#
+# t = gettext.translation(
+# 'pytz', os.path.join(os.path.dirname(__file__), 'locales'),
+# fallback=True
+# )
+# def _(timezone_name):
+# """Translate a timezone name using the current locale, returning Unicode"""
+# return t.ugettext(timezone_name)
+
+
+_tzinfo_cache = {}
+
+def timezone(zone):
+ r''' Return a datetime.tzinfo implementation for the given timezone
+
+ >>> from datetime import datetime, timedelta
+ >>> utc = timezone('UTC')
+ >>> eastern = timezone('US/Eastern')
+ >>> eastern.zone
+ 'US/Eastern'
+ >>> timezone(unicode('US/Eastern')) is eastern
+ True
+ >>> utc_dt = datetime(2002, 10, 27, 6, 0, 0, tzinfo=utc)
+ >>> loc_dt = utc_dt.astimezone(eastern)
+ >>> fmt = '%Y-%m-%d %H:%M:%S %Z (%z)'
+ >>> loc_dt.strftime(fmt)
+ '2002-10-27 01:00:00 EST (-0500)'
+ >>> (loc_dt - timedelta(minutes=10)).strftime(fmt)
+ '2002-10-27 00:50:00 EST (-0500)'
+ >>> eastern.normalize(loc_dt - timedelta(minutes=10)).strftime(fmt)
+ '2002-10-27 01:50:00 EDT (-0400)'
+ >>> (loc_dt + timedelta(minutes=10)).strftime(fmt)
+ '2002-10-27 01:10:00 EST (-0500)'
+
+ Raises UnknownTimeZoneError if passed an unknown zone.
+
+ >>> try:
+ ... timezone('Asia/Shangri-La')
+ ... except UnknownTimeZoneError:
+ ... print('Unknown')
+ Unknown
+
+ >>> try:
+ ... timezone(unicode('\N{TRADE MARK SIGN}'))
+ ... except UnknownTimeZoneError:
+ ... print('Unknown')
+ Unknown
+
+ '''
+ if zone.upper() == 'UTC':
+ return utc
+
+ try:
+ zone = ascii(zone)
+ except UnicodeEncodeError:
+ # All valid timezones are ASCII
+ raise UnknownTimeZoneError(zone)
+
+ zone = _unmunge_zone(zone)
+ if zone not in _tzinfo_cache:
+ if zone in all_timezones_set:
+ fp = open_resource(zone)
+ try:
+ _tzinfo_cache[zone] = build_tzinfo(zone, fp)
+ finally:
+ fp.close()
+ else:
+ raise UnknownTimeZoneError(zone)
+
+ return _tzinfo_cache[zone]
+
+
+def _unmunge_zone(zone):
+ """Undo the time zone name munging done by older versions of pytz."""
+ return zone.replace('_plus_', '+').replace('_minus_', '-')
+
+
+ZERO = datetime.timedelta(0)
+HOUR = datetime.timedelta(hours=1)
+
+
+class UTC(datetime.tzinfo):
+ """UTC
+
+ Optimized UTC implementation. It unpickles using the single module global
+ instance defined beneath this class declaration.
+ """
+ zone = "UTC"
+
+ _utcoffset = ZERO
+ _dst = ZERO
+ _tzname = zone
+
+ def fromutc(self, dt):
+ if dt.tzinfo is None:
+ return self.localize(dt)
+ return super(utc.__class__, self).fromutc(dt)
+
+ def utcoffset(self, dt):
+ return ZERO
+
+ def tzname(self, dt):
+ return "UTC"
+
+ def dst(self, dt):
+ return ZERO
+
+ def __reduce__(self):
+ return _UTC, ()
+
+ def localize(self, dt, is_dst=False):
+ '''Convert naive time to local time'''
+ if dt.tzinfo is not None:
+ raise ValueError('Not naive datetime (tzinfo is already set)')
+ return dt.replace(tzinfo=self)
+
+ def normalize(self, dt, is_dst=False):
+ '''Correct the timezone information on the given datetime'''
+ if dt.tzinfo is self:
+ return dt
+ if dt.tzinfo is None:
+ raise ValueError('Naive time - no tzinfo set')
+ return dt.astimezone(self)
+
+ def __repr__(self):
+ return "<UTC>"
+
+ def __str__(self):
+ return "UTC"
+
+
+UTC = utc = UTC() # UTC is a singleton
+
+
+def _UTC():
+ """Factory function for utc unpickling.
+
+ Makes sure that unpickling a utc instance always returns the same
+ module global.
+
+ These examples belong in the UTC class above, but it is obscured; or in
+ the README.txt, but we are not depending on Python 2.4 so integrating
+ the README.txt examples with the unit tests is not trivial.
+
+ >>> import datetime, pickle
+ >>> dt = datetime.datetime(2005, 3, 1, 14, 13, 21, tzinfo=utc)
+ >>> naive = dt.replace(tzinfo=None)
+ >>> p = pickle.dumps(dt, 1)
+ >>> naive_p = pickle.dumps(naive, 1)
+ >>> len(p) - len(naive_p)
+ 17
+ >>> new = pickle.loads(p)
+ >>> new == dt
+ True
+ >>> new is dt
+ False
+ >>> new.tzinfo is dt.tzinfo
+ True
+ >>> utc is UTC is timezone('UTC')
+ True
+ >>> utc is timezone('GMT')
+ False
+ """
+ return utc
+_UTC.__safe_for_unpickling__ = True
+
+
+def _p(*args):
+ """Factory function for unpickling pytz tzinfo instances.
+
+ Just a wrapper around tzinfo.unpickler to save a few bytes in each pickle
+ by shortening the path.
+ """
+ return unpickler(*args)
+_p.__safe_for_unpickling__ = True
+
+
+
+class _CountryTimezoneDict(LazyDict):
+ """Map ISO 3166 country code to a list of timezone names commonly used
+ in that country.
+
+ iso3166_code is the two letter code used to identify the country.
+
+ >>> def print_list(list_of_strings):
+ ... 'We use a helper so doctests work under Python 2.3 -> 3.x'
+ ... for s in list_of_strings:
+ ... print(s)
+
+ >>> print_list(country_timezones['nz'])
+ Pacific/Auckland
+ Pacific/Chatham
+ >>> print_list(country_timezones['ch'])
+ Europe/Zurich
+ >>> print_list(country_timezones['CH'])
+ Europe/Zurich
+ >>> print_list(country_timezones[unicode('ch')])
+ Europe/Zurich
+ >>> print_list(country_timezones['XXX'])
+ Traceback (most recent call last):
+ ...
+ KeyError: 'XXX'
+
+ Previously, this information was exposed as a function rather than a
+ dictionary. This is still supported::
+
+ >>> print_list(country_timezones('nz'))
+ Pacific/Auckland
+ Pacific/Chatham
+ """
+ def __call__(self, iso3166_code):
+ """Backwards compatibility."""
+ return self[iso3166_code]
+
+ def _fill(self):
+ data = {}
+ zone_tab = open_resource('zone.tab')
+ try:
+ for line in zone_tab:
+ line = line.decode('US-ASCII')
+ if line.startswith('#'):
+ continue
+ code, coordinates, zone = line.split(None, 4)[:3]
+ if zone not in all_timezones_set:
+ continue
+ try:
+ data[code].append(zone)
+ except KeyError:
+ data[code] = [zone]
+ self.data = data
+ finally:
+ zone_tab.close()
+
+country_timezones = _CountryTimezoneDict()
+
+
+class _CountryNameDict(LazyDict):
+ '''Dictionary proving ISO3166 code -> English name.
+
+ >>> print(country_names['au'])
+ Australia
+ '''
+ def _fill(self):
+ data = {}
+ zone_tab = open_resource('iso3166.tab')
+ try:
+ for line in zone_tab.readlines():
+ line = line.decode('US-ASCII')
+ if line.startswith('#'):
+ continue
+ code, name = line.split(None, 1)
+ data[code] = name.strip()
+ self.data = data
+ finally:
+ zone_tab.close()
+
+country_names = _CountryNameDict()
+
+
+# Time-zone info based solely on fixed offsets
+
+class _FixedOffset(datetime.tzinfo):
+
+ zone = None # to match the standard pytz API
+
+ def __init__(self, minutes):
+ if abs(minutes) >= 1440:
+ raise ValueError("absolute offset is too large", minutes)
+ self._minutes = minutes
+ self._offset = datetime.timedelta(minutes=minutes)
+
+ def utcoffset(self, dt):
+ return self._offset
+
+ def __reduce__(self):
+ return FixedOffset, (self._minutes, )
+
+ def dst(self, dt):
+ return ZERO
+
+ def tzname(self, dt):
+ return None
+
+ def __repr__(self):
+ return 'pytz.FixedOffset(%d)' % self._minutes
+
+ def localize(self, dt, is_dst=False):
+ '''Convert naive time to local time'''
+ if dt.tzinfo is not None:
+ raise ValueError('Not naive datetime (tzinfo is already set)')
+ return dt.replace(tzinfo=self)
+
+ def normalize(self, dt, is_dst=False):
+ '''Correct the timezone information on the given datetime'''
+ if dt.tzinfo is None:
+ raise ValueError('Naive time - no tzinfo set')
+ return dt.replace(tzinfo=self)
+
+
+def FixedOffset(offset, _tzinfos = {}):
+ """return a fixed-offset timezone based off a number of minutes.
+
+ >>> one = FixedOffset(-330)
+ >>> one
+ pytz.FixedOffset(-330)
+ >>> one.utcoffset(datetime.datetime.now())
+ datetime.timedelta(-1, 66600)
+ >>> one.dst(datetime.datetime.now())
+ datetime.timedelta(0)
+
+ >>> two = FixedOffset(1380)
+ >>> two
+ pytz.FixedOffset(1380)
+ >>> two.utcoffset(datetime.datetime.now())
+ datetime.timedelta(0, 82800)
+ >>> two.dst(datetime.datetime.now())
+ datetime.timedelta(0)
+
+ The datetime.timedelta must be between the range of -1 and 1 day,
+ non-inclusive.
+
+ >>> FixedOffset(1440)
+ Traceback (most recent call last):
+ ...
+ ValueError: ('absolute offset is too large', 1440)
+
+ >>> FixedOffset(-1440)
+ Traceback (most recent call last):
+ ...
+ ValueError: ('absolute offset is too large', -1440)
+
+ An offset of 0 is special-cased to return UTC.
+
+ >>> FixedOffset(0) is UTC
+ True
+
+ There should always be only one instance of a FixedOffset per timedelta.
+ This should be true for multiple creation calls.
+
+ >>> FixedOffset(-330) is one
+ True
+ >>> FixedOffset(1380) is two
+ True
+
+ It should also be true for pickling.
+
+ >>> import pickle
+ >>> pickle.loads(pickle.dumps(one)) is one
+ True
+ >>> pickle.loads(pickle.dumps(two)) is two
+ True
+ """
+ if offset == 0:
+ return UTC
+
+ info = _tzinfos.get(offset)
+ if info is None:
+ # We haven't seen this one before. we need to save it.
+
+ # Use setdefault to avoid a race condition and make sure we have
+ # only one
+ info = _tzinfos.setdefault(offset, _FixedOffset(offset))
+
+ return info
+
+FixedOffset.__safe_for_unpickling__ = True
+
+
+def _test():
+ import doctest, os, sys
+ sys.path.insert(0, os.pardir)
+ import pytz
+ return doctest.testmod(pytz)
+
+if __name__ == '__main__':
+ _test()
+
+all_timezones = \
+['Africa/Abidjan',
+ 'Africa/Accra',
+ 'Africa/Addis_Ababa',
+ 'Africa/Algiers',
+ 'Africa/Asmara',
+ 'Africa/Asmera',
+ 'Africa/Bamako',
+ 'Africa/Bangui',
+ 'Africa/Banjul',
+ 'Africa/Bissau',
+ 'Africa/Blantyre',
+ 'Africa/Brazzaville',
+ 'Africa/Bujumbura',
+ 'Africa/Cairo',
+ 'Africa/Casablanca',
+ 'Africa/Ceuta',
+ 'Africa/Conakry',
+ 'Africa/Dakar',
+ 'Africa/Dar_es_Salaam',
+ 'Africa/Djibouti',
+ 'Africa/Douala',
+ 'Africa/El_Aaiun',
+ 'Africa/Freetown',
+ 'Africa/Gaborone',
+ 'Africa/Harare',
+ 'Africa/Johannesburg',
+ 'Africa/Juba',
+ 'Africa/Kampala',
+ 'Africa/Khartoum',
+ 'Africa/Kigali',
+ 'Africa/Kinshasa',
+ 'Africa/Lagos',
+ 'Africa/Libreville',
+ 'Africa/Lome',
+ 'Africa/Luanda',
+ 'Africa/Lubumbashi',
+ 'Africa/Lusaka',
+ 'Africa/Malabo',
+ 'Africa/Maputo',
+ 'Africa/Maseru',
+ 'Africa/Mbabane',
+ 'Africa/Mogadishu',
+ 'Africa/Monrovia',
+ 'Africa/Nairobi',
+ 'Africa/Ndjamena',
+ 'Africa/Niamey',
+ 'Africa/Nouakchott',
+ 'Africa/Ouagadougou',
+ 'Africa/Porto-Novo',
+ 'Africa/Sao_Tome',
+ 'Africa/Timbuktu',
+ 'Africa/Tripoli',
+ 'Africa/Tunis',
+ 'Africa/Windhoek',
+ 'America/Adak',
+ 'America/Anchorage',
+ 'America/Anguilla',
+ 'America/Antigua',
+ 'America/Araguaina',
+ 'America/Argentina/Buenos_Aires',
+ 'America/Argentina/Catamarca',
+ 'America/Argentina/ComodRivadavia',
+ 'America/Argentina/Cordoba',
+ 'America/Argentina/Jujuy',
+ 'America/Argentina/La_Rioja',
+ 'America/Argentina/Mendoza',
+ 'America/Argentina/Rio_Gallegos',
+ 'America/Argentina/Salta',
+ 'America/Argentina/San_Juan',
+ 'America/Argentina/San_Luis',
+ 'America/Argentina/Tucuman',
+ 'America/Argentina/Ushuaia',
+ 'America/Aruba',
+ 'America/Asuncion',
+ 'America/Atikokan',
+ 'America/Atka',
+ 'America/Bahia',
+ 'America/Bahia_Banderas',
+ 'America/Barbados',
+ 'America/Belem',
+ 'America/Belize',
+ 'America/Blanc-Sablon',
+ 'America/Boa_Vista',
+ 'America/Bogota',
+ 'America/Boise',
+ 'America/Buenos_Aires',
+ 'America/Cambridge_Bay',
+ 'America/Campo_Grande',
+ 'America/Cancun',
+ 'America/Caracas',
+ 'America/Catamarca',
+ 'America/Cayenne',
+ 'America/Cayman',
+ 'America/Chicago',
+ 'America/Chihuahua',
+ 'America/Coral_Harbour',
+ 'America/Cordoba',
+ 'America/Costa_Rica',
+ 'America/Creston',
+ 'America/Cuiaba',
+ 'America/Curacao',
+ 'America/Danmarkshavn',
+ 'America/Dawson',
+ 'America/Dawson_Creek',
+ 'America/Denver',
+ 'America/Detroit',
+ 'America/Dominica',
+ 'America/Edmonton',
+ 'America/Eirunepe',
+ 'America/El_Salvador',
+ 'America/Ensenada',
+ 'America/Fort_Wayne',
+ 'America/Fortaleza',
+ 'America/Glace_Bay',
+ 'America/Godthab',
+ 'America/Goose_Bay',
+ 'America/Grand_Turk',
+ 'America/Grenada',
+ 'America/Guadeloupe',
+ 'America/Guatemala',
+ 'America/Guayaquil',
+ 'America/Guyana',
+ 'America/Halifax',
+ 'America/Havana',
+ 'America/Hermosillo',
+ 'America/Indiana/Indianapolis',
+ 'America/Indiana/Knox',
+ 'America/Indiana/Marengo',
+ 'America/Indiana/Petersburg',
+ 'America/Indiana/Tell_City',
+ 'America/Indiana/Vevay',
+ 'America/Indiana/Vincennes',
+ 'America/Indiana/Winamac',
+ 'America/Indianapolis',
+ 'America/Inuvik',
+ 'America/Iqaluit',
+ 'America/Jamaica',
+ 'America/Jujuy',
+ 'America/Juneau',
+ 'America/Kentucky/Louisville',
+ 'America/Kentucky/Monticello',
+ 'America/Knox_IN',
+ 'America/Kralendijk',
+ 'America/La_Paz',
+ 'America/Lima',
+ 'America/Los_Angeles',
+ 'America/Louisville',
+ 'America/Lower_Princes',
+ 'America/Maceio',
+ 'America/Managua',
+ 'America/Manaus',
+ 'America/Marigot',
+ 'America/Martinique',
+ 'America/Matamoros',
+ 'America/Mazatlan',
+ 'America/Mendoza',
+ 'America/Menominee',
+ 'America/Merida',
+ 'America/Metlakatla',
+ 'America/Mexico_City',
+ 'America/Miquelon',
+ 'America/Moncton',
+ 'America/Monterrey',
+ 'America/Montevideo',
+ 'America/Montreal',
+ 'America/Montserrat',
+ 'America/Nassau',
+ 'America/New_York',
+ 'America/Nipigon',
+ 'America/Nome',
+ 'America/Noronha',
+ 'America/North_Dakota/Beulah',
+ 'America/North_Dakota/Center',
+ 'America/North_Dakota/New_Salem',
+ 'America/Ojinaga',
+ 'America/Panama',
+ 'America/Pangnirtung',
+ 'America/Paramaribo',
+ 'America/Phoenix',
+ 'America/Port-au-Prince',
+ 'America/Port_of_Spain',
+ 'America/Porto_Acre',
+ 'America/Porto_Velho',
+ 'America/Puerto_Rico',
+ 'America/Rainy_River',
+ 'America/Rankin_Inlet',
+ 'America/Recife',
+ 'America/Regina',
+ 'America/Resolute',
+ 'America/Rio_Branco',
+ 'America/Rosario',
+ 'America/Santa_Isabel',
+ 'America/Santarem',
+ 'America/Santiago',
+ 'America/Santo_Domingo',
+ 'America/Sao_Paulo',
+ 'America/Scoresbysund',
+ 'America/Shiprock',
+ 'America/Sitka',
+ 'America/St_Barthelemy',
+ 'America/St_Johns',
+ 'America/St_Kitts',
+ 'America/St_Lucia',
+ 'America/St_Thomas',
+ 'America/St_Vincent',
+ 'America/Swift_Current',
+ 'America/Tegucigalpa',
+ 'America/Thule',
+ 'America/Thunder_Bay',
+ 'America/Tijuana',
+ 'America/Toronto',
+ 'America/Tortola',
+ 'America/Vancouver',
+ 'America/Virgin',
+ 'America/Whitehorse',
+ 'America/Winnipeg',
+ 'America/Yakutat',
+ 'America/Yellowknife',
+ 'Antarctica/Casey',
+ 'Antarctica/Davis',
+ 'Antarctica/DumontDUrville',
+ 'Antarctica/Macquarie',
+ 'Antarctica/Mawson',
+ 'Antarctica/McMurdo',
+ 'Antarctica/Palmer',
+ 'Antarctica/Rothera',
+ 'Antarctica/South_Pole',
+ 'Antarctica/Syowa',
+ 'Antarctica/Troll',
+ 'Antarctica/Vostok',
+ 'Arctic/Longyearbyen',
+ 'Asia/Aden',
+ 'Asia/Almaty',
+ 'Asia/Amman',
+ 'Asia/Anadyr',
+ 'Asia/Aqtau',
+ 'Asia/Aqtobe',
+ 'Asia/Ashgabat',
+ 'Asia/Ashkhabad',
+ 'Asia/Baghdad',
+ 'Asia/Bahrain',
+ 'Asia/Baku',
+ 'Asia/Bangkok',
+ 'Asia/Beirut',
+ 'Asia/Bishkek',
+ 'Asia/Brunei',
+ 'Asia/Calcutta',
+ 'Asia/Chita',
+ 'Asia/Choibalsan',
+ 'Asia/Chongqing',
+ 'Asia/Chungking',
+ 'Asia/Colombo',
+ 'Asia/Dacca',
+ 'Asia/Damascus',
+ 'Asia/Dhaka',
+ 'Asia/Dili',
+ 'Asia/Dubai',
+ 'Asia/Dushanbe',
+ 'Asia/Gaza',
+ 'Asia/Harbin',
+ 'Asia/Hebron',
+ 'Asia/Ho_Chi_Minh',
+ 'Asia/Hong_Kong',
+ 'Asia/Hovd',
+ 'Asia/Irkutsk',
+ 'Asia/Istanbul',
+ 'Asia/Jakarta',
+ 'Asia/Jayapura',
+ 'Asia/Jerusalem',
+ 'Asia/Kabul',
+ 'Asia/Kamchatka',
+ 'Asia/Karachi',
+ 'Asia/Kashgar',
+ 'Asia/Kathmandu',
+ 'Asia/Katmandu',
+ 'Asia/Khandyga',
+ 'Asia/Kolkata',
+ 'Asia/Krasnoyarsk',
+ 'Asia/Kuala_Lumpur',
+ 'Asia/Kuching',
+ 'Asia/Kuwait',
+ 'Asia/Macao',
+ 'Asia/Macau',
+ 'Asia/Magadan',
+ 'Asia/Makassar',
+ 'Asia/Manila',
+ 'Asia/Muscat',
+ 'Asia/Nicosia',
+ 'Asia/Novokuznetsk',
+ 'Asia/Novosibirsk',
+ 'Asia/Omsk',
+ 'Asia/Oral',
+ 'Asia/Phnom_Penh',
+ 'Asia/Pontianak',
+ 'Asia/Pyongyang',
+ 'Asia/Qatar',
+ 'Asia/Qyzylorda',
+ 'Asia/Rangoon',
+ 'Asia/Riyadh',
+ 'Asia/Saigon',
+ 'Asia/Sakhalin',
+ 'Asia/Samarkand',
+ 'Asia/Seoul',
+ 'Asia/Shanghai',
+ 'Asia/Singapore',
+ 'Asia/Srednekolymsk',
+ 'Asia/Taipei',
+ 'Asia/Tashkent',
+ 'Asia/Tbilisi',
+ 'Asia/Tehran',
+ 'Asia/Tel_Aviv',
+ 'Asia/Thimbu',
+ 'Asia/Thimphu',
+ 'Asia/Tokyo',
+ 'Asia/Ujung_Pandang',
+ 'Asia/Ulaanbaatar',
+ 'Asia/Ulan_Bator',
+ 'Asia/Urumqi',
+ 'Asia/Ust-Nera',
+ 'Asia/Vientiane',
+ 'Asia/Vladivostok',
+ 'Asia/Yakutsk',
+ 'Asia/Yekaterinburg',
+ 'Asia/Yerevan',
+ 'Atlantic/Azores',
+ 'Atlantic/Bermuda',
+ 'Atlantic/Canary',
+ 'Atlantic/Cape_Verde',
+ 'Atlantic/Faeroe',
+ 'Atlantic/Faroe',
+ 'Atlantic/Jan_Mayen',
+ 'Atlantic/Madeira',
+ 'Atlantic/Reykjavik',
+ 'Atlantic/South_Georgia',
+ 'Atlantic/St_Helena',
+ 'Atlantic/Stanley',
+ 'Australia/ACT',
+ 'Australia/Adelaide',
+ 'Australia/Brisbane',
+ 'Australia/Broken_Hill',
+ 'Australia/Canberra',
+ 'Australia/Currie',
+ 'Australia/Darwin',
+ 'Australia/Eucla',
+ 'Australia/Hobart',
+ 'Australia/LHI',
+ 'Australia/Lindeman',
+ 'Australia/Lord_Howe',
+ 'Australia/Melbourne',
+ 'Australia/NSW',
+ 'Australia/North',
+ 'Australia/Perth',
+ 'Australia/Queensland',
+ 'Australia/South',
+ 'Australia/Sydney',
+ 'Australia/Tasmania',
+ 'Australia/Victoria',
+ 'Australia/West',
+ 'Australia/Yancowinna',
+ 'Brazil/Acre',
+ 'Brazil/DeNoronha',
+ 'Brazil/East',
+ 'Brazil/West',
+ 'CET',
+ 'CST6CDT',
+ 'Canada/Atlantic',
+ 'Canada/Central',
+ 'Canada/East-Saskatchewan',
+ 'Canada/Eastern',
+ 'Canada/Mountain',
+ 'Canada/Newfoundland',
+ 'Canada/Pacific',
+ 'Canada/Saskatchewan',
+ 'Canada/Yukon',
+ 'Chile/Continental',
+ 'Chile/EasterIsland',
+ 'Cuba',
+ 'EET',
+ 'EST',
+ 'EST5EDT',
+ 'Egypt',
+ 'Eire',
+ 'Etc/GMT',
+ 'Etc/GMT+0',
+ 'Etc/GMT+1',
+ 'Etc/GMT+10',
+ 'Etc/GMT+11',
+ 'Etc/GMT+12',
+ 'Etc/GMT+2',
+ 'Etc/GMT+3',
+ 'Etc/GMT+4',
+ 'Etc/GMT+5',
+ 'Etc/GMT+6',
+ 'Etc/GMT+7',
+ 'Etc/GMT+8',
+ 'Etc/GMT+9',
+ 'Etc/GMT-0',
+ 'Etc/GMT-1',
+ 'Etc/GMT-10',
+ 'Etc/GMT-11',
+ 'Etc/GMT-12',
+ 'Etc/GMT-13',
+ 'Etc/GMT-14',
+ 'Etc/GMT-2',
+ 'Etc/GMT-3',
+ 'Etc/GMT-4',
+ 'Etc/GMT-5',
+ 'Etc/GMT-6',
+ 'Etc/GMT-7',
+ 'Etc/GMT-8',
+ 'Etc/GMT-9',
+ 'Etc/GMT0',
+ 'Etc/Greenwich',
+ 'Etc/UCT',
+ 'Etc/UTC',
+ 'Etc/Universal',
+ 'Etc/Zulu',
+ 'Europe/Amsterdam',
+ 'Europe/Andorra',
+ 'Europe/Athens',
+ 'Europe/Belfast',
+ 'Europe/Belgrade',
+ 'Europe/Berlin',
+ 'Europe/Bratislava',
+ 'Europe/Brussels',
+ 'Europe/Bucharest',
+ 'Europe/Budapest',
+ 'Europe/Busingen',
+ 'Europe/Chisinau',
+ 'Europe/Copenhagen',
+ 'Europe/Dublin',
+ 'Europe/Gibraltar',
+ 'Europe/Guernsey',
+ 'Europe/Helsinki',
+ 'Europe/Isle_of_Man',
+ 'Europe/Istanbul',
+ 'Europe/Jersey',
+ 'Europe/Kaliningrad',
+ 'Europe/Kiev',
+ 'Europe/Lisbon',
+ 'Europe/Ljubljana',
+ 'Europe/London',
+ 'Europe/Luxembourg',
+ 'Europe/Madrid',
+ 'Europe/Malta',
+ 'Europe/Mariehamn',
+ 'Europe/Minsk',
+ 'Europe/Monaco',
+ 'Europe/Moscow',
+ 'Europe/Nicosia',
+ 'Europe/Oslo',
+ 'Europe/Paris',
+ 'Europe/Podgorica',
+ 'Europe/Prague',
+ 'Europe/Riga',
+ 'Europe/Rome',
+ 'Europe/Samara',
+ 'Europe/San_Marino',
+ 'Europe/Sarajevo',
+ 'Europe/Simferopol',
+ 'Europe/Skopje',
+ 'Europe/Sofia',
+ 'Europe/Stockholm',
+ 'Europe/Tallinn',
+ 'Europe/Tirane',
+ 'Europe/Tiraspol',
+ 'Europe/Uzhgorod',
+ 'Europe/Vaduz',
+ 'Europe/Vatican',
+ 'Europe/Vienna',
+ 'Europe/Vilnius',
+ 'Europe/Volgograd',
+ 'Europe/Warsaw',
+ 'Europe/Zagreb',
+ 'Europe/Zaporozhye',
+ 'Europe/Zurich',
+ 'GB',
+ 'GB-Eire',
+ 'GMT',
+ 'GMT+0',
+ 'GMT-0',
+ 'GMT0',
+ 'Greenwich',
+ 'HST',
+ 'Hongkong',
+ 'Iceland',
+ 'Indian/Antananarivo',
+ 'Indian/Chagos',
+ 'Indian/Christmas',
+ 'Indian/Cocos',
+ 'Indian/Comoro',
+ 'Indian/Kerguelen',
+ 'Indian/Mahe',
+ 'Indian/Maldives',
+ 'Indian/Mauritius',
+ 'Indian/Mayotte',
+ 'Indian/Reunion',
+ 'Iran',
+ 'Israel',
+ 'Jamaica',
+ 'Japan',
+ 'Kwajalein',
+ 'Libya',
+ 'MET',
+ 'MST',
+ 'MST7MDT',
+ 'Mexico/BajaNorte',
+ 'Mexico/BajaSur',
+ 'Mexico/General',
+ 'NZ',
+ 'NZ-CHAT',
+ 'Navajo',
+ 'PRC',
+ 'PST8PDT',
+ 'Pacific/Apia',
+ 'Pacific/Auckland',
+ 'Pacific/Bougainville',
+ 'Pacific/Chatham',
+ 'Pacific/Chuuk',
+ 'Pacific/Easter',
+ 'Pacific/Efate',
+ 'Pacific/Enderbury',
+ 'Pacific/Fakaofo',
+ 'Pacific/Fiji',
+ 'Pacific/Funafuti',
+ 'Pacific/Galapagos',
+ 'Pacific/Gambier',
+ 'Pacific/Guadalcanal',
+ 'Pacific/Guam',
+ 'Pacific/Honolulu',
+ 'Pacific/Johnston',
+ 'Pacific/Kiritimati',
+ 'Pacific/Kosrae',
+ 'Pacific/Kwajalein',
+ 'Pacific/Majuro',
+ 'Pacific/Marquesas',
+ 'Pacific/Midway',
+ 'Pacific/Nauru',
+ 'Pacific/Niue',
+ 'Pacific/Norfolk',
+ 'Pacific/Noumea',
+ 'Pacific/Pago_Pago',
+ 'Pacific/Palau',
+ 'Pacific/Pitcairn',
+ 'Pacific/Pohnpei',
+ 'Pacific/Ponape',
+ 'Pacific/Port_Moresby',
+ 'Pacific/Rarotonga',
+ 'Pacific/Saipan',
+ 'Pacific/Samoa',
+ 'Pacific/Tahiti',
+ 'Pacific/Tarawa',
+ 'Pacific/Tongatapu',
+ 'Pacific/Truk',
+ 'Pacific/Wake',
+ 'Pacific/Wallis',
+ 'Pacific/Yap',
+ 'Poland',
+ 'Portugal',
+ 'ROC',
+ 'ROK',
+ 'Singapore',
+ 'Turkey',
+ 'UCT',
+ 'US/Alaska',
+ 'US/Aleutian',
+ 'US/Arizona',
+ 'US/Central',
+ 'US/East-Indiana',
+ 'US/Eastern',
+ 'US/Hawaii',
+ 'US/Indiana-Starke',
+ 'US/Michigan',
+ 'US/Mountain',
+ 'US/Pacific',
+ 'US/Pacific-New',
+ 'US/Samoa',
+ 'UTC',
+ 'Universal',
+ 'W-SU',
+ 'WET',
+ 'Zulu']
+all_timezones = LazyList(
+ tz for tz in all_timezones if resource_exists(tz))
+
+all_timezones_set = LazySet(all_timezones)
+common_timezones = \
+['Africa/Abidjan',
+ 'Africa/Accra',
+ 'Africa/Addis_Ababa',
+ 'Africa/Algiers',
+ 'Africa/Asmara',
+ 'Africa/Bamako',
+ 'Africa/Bangui',
+ 'Africa/Banjul',
+ 'Africa/Bissau',
+ 'Africa/Blantyre',
+ 'Africa/Brazzaville',
+ 'Africa/Bujumbura',
+ 'Africa/Cairo',
+ 'Africa/Casablanca',
+ 'Africa/Ceuta',
+ 'Africa/Conakry',
+ 'Africa/Dakar',
+ 'Africa/Dar_es_Salaam',
+ 'Africa/Djibouti',
+ 'Africa/Douala',
+ 'Africa/El_Aaiun',
+ 'Africa/Freetown',
+ 'Africa/Gaborone',
+ 'Africa/Harare',
+ 'Africa/Johannesburg',
+ 'Africa/Juba',
+ 'Africa/Kampala',
+ 'Africa/Khartoum',
+ 'Africa/Kigali',
+ 'Africa/Kinshasa',
+ 'Africa/Lagos',
+ 'Africa/Libreville',
+ 'Africa/Lome',
+ 'Africa/Luanda',
+ 'Africa/Lubumbashi',
+ 'Africa/Lusaka',
+ 'Africa/Malabo',
+ 'Africa/Maputo',
+ 'Africa/Maseru',
+ 'Africa/Mbabane',
+ 'Africa/Mogadishu',
+ 'Africa/Monrovia',
+ 'Africa/Nairobi',
+ 'Africa/Ndjamena',
+ 'Africa/Niamey',
+ 'Africa/Nouakchott',
+ 'Africa/Ouagadougou',
+ 'Africa/Porto-Novo',
+ 'Africa/Sao_Tome',
+ 'Africa/Tripoli',
+ 'Africa/Tunis',
+ 'Africa/Windhoek',
+ 'America/Adak',
+ 'America/Anchorage',
+ 'America/Anguilla',
+ 'America/Antigua',
+ 'America/Araguaina',
+ 'America/Argentina/Buenos_Aires',
+ 'America/Argentina/Catamarca',
+ 'America/Argentina/Cordoba',
+ 'America/Argentina/Jujuy',
+ 'America/Argentina/La_Rioja',
+ 'America/Argentina/Mendoza',
+ 'America/Argentina/Rio_Gallegos',
+ 'America/Argentina/Salta',
+ 'America/Argentina/San_Juan',
+ 'America/Argentina/San_Luis',
+ 'America/Argentina/Tucuman',
+ 'America/Argentina/Ushuaia',
+ 'America/Aruba',
+ 'America/Asuncion',
+ 'America/Atikokan',
+ 'America/Bahia',
+ 'America/Bahia_Banderas',
+ 'America/Barbados',
+ 'America/Belem',
+ 'America/Belize',
+ 'America/Blanc-Sablon',
+ 'America/Boa_Vista',
+ 'America/Bogota',
+ 'America/Boise',
+ 'America/Cambridge_Bay',
+ 'America/Campo_Grande',
+ 'America/Cancun',
+ 'America/Caracas',
+ 'America/Cayenne',
+ 'America/Cayman',
+ 'America/Chicago',
+ 'America/Chihuahua',
+ 'America/Costa_Rica',
+ 'America/Creston',
+ 'America/Cuiaba',
+ 'America/Curacao',
+ 'America/Danmarkshavn',
+ 'America/Dawson',
+ 'America/Dawson_Creek',
+ 'America/Denver',
+ 'America/Detroit',
+ 'America/Dominica',
+ 'America/Edmonton',
+ 'America/Eirunepe',
+ 'America/El_Salvador',
+ 'America/Fortaleza',
+ 'America/Glace_Bay',
+ 'America/Godthab',
+ 'America/Goose_Bay',
+ 'America/Grand_Turk',
+ 'America/Grenada',
+ 'America/Guadeloupe',
+ 'America/Guatemala',
+ 'America/Guayaquil',
+ 'America/Guyana',
+ 'America/Halifax',
+ 'America/Havana',
+ 'America/Hermosillo',
+ 'America/Indiana/Indianapolis',
+ 'America/Indiana/Knox',
+ 'America/Indiana/Marengo',
+ 'America/Indiana/Petersburg',
+ 'America/Indiana/Tell_City',
+ 'America/Indiana/Vevay',
+ 'America/Indiana/Vincennes',
+ 'America/Indiana/Winamac',
+ 'America/Inuvik',
+ 'America/Iqaluit',
+ 'America/Jamaica',
+ 'America/Juneau',
+ 'America/Kentucky/Louisville',
+ 'America/Kentucky/Monticello',
+ 'America/Kralendijk',
+ 'America/La_Paz',
+ 'America/Lima',
+ 'America/Los_Angeles',
+ 'America/Lower_Princes',
+ 'America/Maceio',
+ 'America/Managua',
+ 'America/Manaus',
+ 'America/Marigot',
+ 'America/Martinique',
+ 'America/Matamoros',
+ 'America/Mazatlan',
+ 'America/Menominee',
+ 'America/Merida',
+ 'America/Metlakatla',
+ 'America/Mexico_City',
+ 'America/Miquelon',
+ 'America/Moncton',
+ 'America/Monterrey',
+ 'America/Montevideo',
+ 'America/Montreal',
+ 'America/Montserrat',
+ 'America/Nassau',
+ 'America/New_York',
+ 'America/Nipigon',
+ 'America/Nome',
+ 'America/Noronha',
+ 'America/North_Dakota/Beulah',
+ 'America/North_Dakota/Center',
+ 'America/North_Dakota/New_Salem',
+ 'America/Ojinaga',
+ 'America/Panama',
+ 'America/Pangnirtung',
+ 'America/Paramaribo',
+ 'America/Phoenix',
+ 'America/Port-au-Prince',
+ 'America/Port_of_Spain',
+ 'America/Porto_Velho',
+ 'America/Puerto_Rico',
+ 'America/Rainy_River',
+ 'America/Rankin_Inlet',
+ 'America/Recife',
+ 'America/Regina',
+ 'America/Resolute',
+ 'America/Rio_Branco',
+ 'America/Santa_Isabel',
+ 'America/Santarem',
+ 'America/Santiago',
+ 'America/Santo_Domingo',
+ 'America/Sao_Paulo',
+ 'America/Scoresbysund',
+ 'America/Sitka',
+ 'America/St_Barthelemy',
+ 'America/St_Johns',
+ 'America/St_Kitts',
+ 'America/St_Lucia',
+ 'America/St_Thomas',
+ 'America/St_Vincent',
+ 'America/Swift_Current',
+ 'America/Tegucigalpa',
+ 'America/Thule',
+ 'America/Thunder_Bay',
+ 'America/Tijuana',
+ 'America/Toronto',
+ 'America/Tortola',
+ 'America/Vancouver',
+ 'America/Whitehorse',
+ 'America/Winnipeg',
+ 'America/Yakutat',
+ 'America/Yellowknife',
+ 'Antarctica/Casey',
+ 'Antarctica/Davis',
+ 'Antarctica/DumontDUrville',
+ 'Antarctica/Macquarie',
+ 'Antarctica/Mawson',
+ 'Antarctica/McMurdo',
+ 'Antarctica/Palmer',
+ 'Antarctica/Rothera',
+ 'Antarctica/Syowa',
+ 'Antarctica/Troll',
+ 'Antarctica/Vostok',
+ 'Arctic/Longyearbyen',
+ 'Asia/Aden',
+ 'Asia/Almaty',
+ 'Asia/Amman',
+ 'Asia/Anadyr',
+ 'Asia/Aqtau',
+ 'Asia/Aqtobe',
+ 'Asia/Ashgabat',
+ 'Asia/Baghdad',
+ 'Asia/Bahrain',
+ 'Asia/Baku',
+ 'Asia/Bangkok',
+ 'Asia/Beirut',
+ 'Asia/Bishkek',
+ 'Asia/Brunei',
+ 'Asia/Chita',
+ 'Asia/Choibalsan',
+ 'Asia/Colombo',
+ 'Asia/Damascus',
+ 'Asia/Dhaka',
+ 'Asia/Dili',
+ 'Asia/Dubai',
+ 'Asia/Dushanbe',
+ 'Asia/Gaza',
+ 'Asia/Hebron',
+ 'Asia/Ho_Chi_Minh',
+ 'Asia/Hong_Kong',
+ 'Asia/Hovd',
+ 'Asia/Irkutsk',
+ 'Asia/Jakarta',
+ 'Asia/Jayapura',
+ 'Asia/Jerusalem',
+ 'Asia/Kabul',
+ 'Asia/Kamchatka',
+ 'Asia/Karachi',
+ 'Asia/Kathmandu',
+ 'Asia/Khandyga',
+ 'Asia/Kolkata',
+ 'Asia/Krasnoyarsk',
+ 'Asia/Kuala_Lumpur',
+ 'Asia/Kuching',
+ 'Asia/Kuwait',
+ 'Asia/Macau',
+ 'Asia/Magadan',
+ 'Asia/Makassar',
+ 'Asia/Manila',
+ 'Asia/Muscat',
+ 'Asia/Nicosia',
+ 'Asia/Novokuznetsk',
+ 'Asia/Novosibirsk',
+ 'Asia/Omsk',
+ 'Asia/Oral',
+ 'Asia/Phnom_Penh',
+ 'Asia/Pontianak',
+ 'Asia/Pyongyang',
+ 'Asia/Qatar',
+ 'Asia/Qyzylorda',
+ 'Asia/Rangoon',
+ 'Asia/Riyadh',
+ 'Asia/Sakhalin',
+ 'Asia/Samarkand',
+ 'Asia/Seoul',
+ 'Asia/Shanghai',
+ 'Asia/Singapore',
+ 'Asia/Srednekolymsk',
+ 'Asia/Taipei',
+ 'Asia/Tashkent',
+ 'Asia/Tbilisi',
+ 'Asia/Tehran',
+ 'Asia/Thimphu',
+ 'Asia/Tokyo',
+ 'Asia/Ulaanbaatar',
+ 'Asia/Urumqi',
+ 'Asia/Ust-Nera',
+ 'Asia/Vientiane',
+ 'Asia/Vladivostok',
+ 'Asia/Yakutsk',
+ 'Asia/Yekaterinburg',
+ 'Asia/Yerevan',
+ 'Atlantic/Azores',
+ 'Atlantic/Bermuda',
+ 'Atlantic/Canary',
+ 'Atlantic/Cape_Verde',
+ 'Atlantic/Faroe',
+ 'Atlantic/Madeira',
+ 'Atlantic/Reykjavik',
+ 'Atlantic/South_Georgia',
+ 'Atlantic/St_Helena',
+ 'Atlantic/Stanley',
+ 'Australia/Adelaide',
+ 'Australia/Brisbane',
+ 'Australia/Broken_Hill',
+ 'Australia/Currie',
+ 'Australia/Darwin',
+ 'Australia/Eucla',
+ 'Australia/Hobart',
+ 'Australia/Lindeman',
+ 'Australia/Lord_Howe',
+ 'Australia/Melbourne',
+ 'Australia/Perth',
+ 'Australia/Sydney',
+ 'Canada/Atlantic',
+ 'Canada/Central',
+ 'Canada/Eastern',
+ 'Canada/Mountain',
+ 'Canada/Newfoundland',
+ 'Canada/Pacific',
+ 'Europe/Amsterdam',
+ 'Europe/Andorra',
+ 'Europe/Athens',
+ 'Europe/Belgrade',
+ 'Europe/Berlin',
+ 'Europe/Bratislava',
+ 'Europe/Brussels',
+ 'Europe/Bucharest',
+ 'Europe/Budapest',
+ 'Europe/Busingen',
+ 'Europe/Chisinau',
+ 'Europe/Copenhagen',
+ 'Europe/Dublin',
+ 'Europe/Gibraltar',
+ 'Europe/Guernsey',
+ 'Europe/Helsinki',
+ 'Europe/Isle_of_Man',
+ 'Europe/Istanbul',
+ 'Europe/Jersey',
+ 'Europe/Kaliningrad',
+ 'Europe/Kiev',
+ 'Europe/Lisbon',
+ 'Europe/Ljubljana',
+ 'Europe/London',
+ 'Europe/Luxembourg',
+ 'Europe/Madrid',
+ 'Europe/Malta',
+ 'Europe/Mariehamn',
+ 'Europe/Minsk',
+ 'Europe/Monaco',
+ 'Europe/Moscow',
+ 'Europe/Oslo',
+ 'Europe/Paris',
+ 'Europe/Podgorica',
+ 'Europe/Prague',
+ 'Europe/Riga',
+ 'Europe/Rome',
+ 'Europe/Samara',
+ 'Europe/San_Marino',
+ 'Europe/Sarajevo',
+ 'Europe/Simferopol',
+ 'Europe/Skopje',
+ 'Europe/Sofia',
+ 'Europe/Stockholm',
+ 'Europe/Tallinn',
+ 'Europe/Tirane',
+ 'Europe/Uzhgorod',
+ 'Europe/Vaduz',
+ 'Europe/Vatican',
+ 'Europe/Vienna',
+ 'Europe/Vilnius',
+ 'Europe/Volgograd',
+ 'Europe/Warsaw',
+ 'Europe/Zagreb',
+ 'Europe/Zaporozhye',
+ 'Europe/Zurich',
+ 'GMT',
+ 'Indian/Antananarivo',
+ 'Indian/Chagos',
+ 'Indian/Christmas',
+ 'Indian/Cocos',
+ 'Indian/Comoro',
+ 'Indian/Kerguelen',
+ 'Indian/Mahe',
+ 'Indian/Maldives',
+ 'Indian/Mauritius',
+ 'Indian/Mayotte',
+ 'Indian/Reunion',
+ 'Pacific/Apia',
+ 'Pacific/Auckland',
+ 'Pacific/Bougainville',
+ 'Pacific/Chatham',
+ 'Pacific/Chuuk',
+ 'Pacific/Easter',
+ 'Pacific/Efate',
+ 'Pacific/Enderbury',
+ 'Pacific/Fakaofo',
+ 'Pacific/Fiji',
+ 'Pacific/Funafuti',
+ 'Pacific/Galapagos',
+ 'Pacific/Gambier',
+ 'Pacific/Guadalcanal',
+ 'Pacific/Guam',
+ 'Pacific/Honolulu',
+ 'Pacific/Johnston',
+ 'Pacific/Kiritimati',
+ 'Pacific/Kosrae',
+ 'Pacific/Kwajalein',
+ 'Pacific/Majuro',
+ 'Pacific/Marquesas',
+ 'Pacific/Midway',
+ 'Pacific/Nauru',
+ 'Pacific/Niue',
+ 'Pacific/Norfolk',
+ 'Pacific/Noumea',
+ 'Pacific/Pago_Pago',
+ 'Pacific/Palau',
+ 'Pacific/Pitcairn',
+ 'Pacific/Pohnpei',
+ 'Pacific/Port_Moresby',
+ 'Pacific/Rarotonga',
+ 'Pacific/Saipan',
+ 'Pacific/Tahiti',
+ 'Pacific/Tarawa',
+ 'Pacific/Tongatapu',
+ 'Pacific/Wake',
+ 'Pacific/Wallis',
+ 'US/Alaska',
+ 'US/Arizona',
+ 'US/Central',
+ 'US/Eastern',
+ 'US/Hawaii',
+ 'US/Mountain',
+ 'US/Pacific',
+ 'UTC']
+common_timezones = LazyList(
+ tz for tz in common_timezones if tz in all_timezones)
+
+common_timezones_set = LazySet(common_timezones)