o <>> from pytz import timezone >>> gmt = timezone('GMT') >>> isinstance(gmt, StaticTzInfo) True >>> dt = datetime(2011, 5, 8, 1, 2, 3, tzinfo=gmt) >>> gmt.normalize(dt) is dt True The supported method of converting between timezones is to use datetime.astimezone(). Currently normalize() also works: >>> la = timezone('America/Los_Angeles') >>> dt = la.localize(datetime(2011, 5, 7, 1, 2, 3)) >>> fmt = '%Y-%m-%d %H:%M:%S %Z (%z)' >>> gmt.normalize(dt).strftime(fmt) '2011-05-07 08:02:03 GMT (+0000)' NNaive time - no tzinfo set)rr1 astimezoner4rrr normalizevs   zStaticTzInfo.normalizecCs d|jfS)Nzr#r%rrr__repr__s zStaticTzInfo.__repr__cCstj|jffSr")pytz_pr$r%rrr __reduce__szStaticTzInfo.__reduce__r"F) r(r)r*__doc__r3r6r9r:r<r?r@rCrrrrr-Ls      r-c@sveZdZdZdZdZdZdZdZdddZ ddZ ddZ dd d Z dd d Z dddZdddZddZddZdS) DstTzInfozA timezone that has a variable offset from UTC The offset might change if daylight saving time comes into effect, or at a point in history when the region decides to change their timezone definition. NcCs||r||_|\|_|_|_dSi}||_|jd\|_|_|_|||jd<|jddD]}||vr;|||||<q-dS)Nrr)_tzinfosr+_dstr,_transition_info __class__)r&_infrGinfrrr__init__szDstTzInfo.__init__cCsl|jdurt|jdd|jurtd|jdd}tdt|j|d}|j|}||dj|j|dS)r.NrGr/r0rr) rgetattrrGr1r2maxr_utc_transition_timesrI)r&ridxrLrrrr3s   zDstTzInfo.fromutccCs8|jdur td|jj}|jdd}||}||S)aICorrect the timezone information on the given datetime If date arithmetic crosses DST boundaries, the tzinfo is not magically adjusted. This method normalizes the tzinfo to the correct one. To test, first we need to do some setup >>> from pytz import timezone >>> utc = timezone('UTC') >>> eastern = timezone('US/Eastern') >>> fmt = '%Y-%m-%d %H:%M:%S %Z (%z)' We next create a datetime right on an end-of-DST transition point, the instant when the wallclocks are wound back one hour. >>> utc_dt = datetime(2002, 10, 27, 6, 0, 0, tzinfo=utc) >>> loc_dt = utc_dt.astimezone(eastern) >>> loc_dt.strftime(fmt) '2002-10-27 01:00:00 EST (-0500)' Now, if we subtract a few minutes from it, note that the timezone information has not changed. >>> before = loc_dt - timedelta(minutes=10) >>> before.strftime(fmt) '2002-10-27 00:50:00 EST (-0500)' But we can fix that by calling the normalize method >>> before = eastern.normalize(before) >>> before.strftime(fmt) '2002-10-27 01:50:00 EDT (-0400)' The supported method of converting between timezones is to use datetime.astimezone(). Currently, normalize() also works: >>> th = timezone('Asia/Bangkok') >>> am = timezone('Europe/Amsterdam') >>> dt = th.localize(datetime(2011, 5, 7, 1, 2, 3)) >>> fmt = '%Y-%m-%d %H:%M:%S %Z (%z)' >>> am.normalize(dt).strftime(fmt) '2011-05-06 20:02:03 CEST (+0200)' Nr=r0)rr1r+r2r3)r&roffsetrrrr?s -  zDstTzInfo.normalizeFc s|jdur tdt}tddtddfD]1}||}tdt|j|d}|j|}|j|}| |j |d}|j dd|krG| |qt |dkrR| St |dkrdur`t|rs|j|tdd d d tdd S|j|tdd d d tdd Sdurt|fd d|D} t | dkr| dSt | dkrt|} i} | D]} | j dd| jj} | | vsJ| | | <q| ttg | S)aConvert naive time to local time. This method should be used to construct localtimes, rather than passing a tzinfo argument to a datetime constructor. is_dst is used to determine the correct timezone in the ambigous period at the end of daylight saving time. >>> from pytz import timezone >>> fmt = '%Y-%m-%d %H:%M:%S %Z (%z)' >>> amdam = timezone('Europe/Amsterdam') >>> dt = datetime(2004, 10, 31, 2, 0, 0) >>> loc_dt1 = amdam.localize(dt, is_dst=True) >>> loc_dt2 = amdam.localize(dt, is_dst=False) >>> loc_dt1.strftime(fmt) '2004-10-31 02:00:00 CEST (+0200)' >>> loc_dt2.strftime(fmt) '2004-10-31 02:00:00 CET (+0100)' >>> str(loc_dt2 - loc_dt1) '1:00:00' Use is_dst=None to raise an AmbiguousTimeError for ambiguous times at the end of daylight saving time >>> try: ... loc_dt1 = amdam.localize(dt, is_dst=None) ... except AmbiguousTimeError: ... print('Ambiguous') Ambiguous is_dst defaults to False >>> amdam.localize(dt) == amdam.localize(dt, False) True is_dst is also used to determine the correct timezone in the wallclock times jumped over at the start of daylight saving time. >>> pacific = timezone('US/Pacific') >>> dt = datetime(2008, 3, 9, 2, 0, 0) >>> ploc_dt1 = pacific.localize(dt, is_dst=True) >>> ploc_dt2 = pacific.localize(dt, is_dst=False) >>> ploc_dt1.strftime(fmt) '2008-03-09 02:00:00 PDT (-0700)' >>> ploc_dt2.strftime(fmt) '2008-03-09 02:00:00 PST (-0800)' >>> str(ploc_dt2 - ploc_dt1) '1:00:00' Use is_dst=None to raise a NonExistentTimeError for these skipped times. >>> try: ... loc_dt1 = pacific.localize(dt, is_dst=None) ... except NonExistentTimeError: ... print('Non-existent') Non-existent Nr;)rrrr0)hoursTr5Fcs g|] }t|jjkr|qSr)boolrrH).0prVrr osz&DstTzInfo.localize..)rr1setrrOrrPrIrGr?r2addlenpoprr<rlistr+min) r&rr5possible_loc_dtr loc_dtrQrLrfiltered_possible_loc_dtdateslocal_dtutc_timerrVrr<sb ;             zDstTzInfo.localizecC0|durdS|j|ur|||}|jjS|jS)aLSee datetime.tzinfo.utcoffset The is_dst parameter may be used to remove ambiguity during DST transitions. >>> from pytz import timezone >>> tz = timezone('America/St_Johns') >>> ambiguous = datetime(2009, 10, 31, 23, 30) >>> str(tz.utcoffset(ambiguous, is_dst=False)) '-1 day, 20:30:00' >>> str(tz.utcoffset(ambiguous, is_dst=True)) '-1 day, 21:30:00' >>> try: ... tz.utcoffset(ambiguous) ... except AmbiguousTimeError: ... print('Ambiguous') Ambiguous N)rr<r+r4rrrr6s   zDstTzInfo.utcoffsetcCrg)aSee datetime.tzinfo.dst The is_dst parameter may be used to remove ambiguity during DST transitions. >>> from pytz import timezone >>> tz = timezone('America/St_Johns') >>> normal = datetime(2009, 9, 1) >>> str(tz.dst(normal)) '1:00:00' >>> str(tz.dst(normal, is_dst=False)) '1:00:00' >>> str(tz.dst(normal, is_dst=True)) '1:00:00' >>> ambiguous = datetime(2009, 10, 31, 23, 30) >>> str(tz.dst(ambiguous, is_dst=False)) '0:00:00' >>> str(tz.dst(ambiguous, is_dst=True)) '1:00:00' >>> try: ... tz.dst(ambiguous) ... except AmbiguousTimeError: ... print('Ambiguous') Ambiguous N)rr<rHr4rrrr9s   z DstTzInfo.dstcCs2|dur|jS|j|ur|||}|jjS|jS)aSee datetime.tzinfo.tzname The is_dst parameter may be used to remove ambiguity during DST transitions. >>> from pytz import timezone >>> tz = timezone('America/St_Johns') >>> normal = datetime(2009, 9, 1) >>> tz.tzname(normal) 'NDT' >>> tz.tzname(normal, is_dst=False) 'NDT' >>> tz.tzname(normal, is_dst=True) 'NDT' >>> ambiguous = datetime(2009, 10, 31, 23, 30) >>> tz.tzname(ambiguous, is_dst=False) 'NST' >>> tz.tzname(ambiguous, is_dst=True) 'NDT' >>> try: ... tz.tzname(ambiguous) ... except AmbiguousTimeError: ... print('Ambiguous') Ambiguous N)r$rr<r,r4rrrr:s   zDstTzInfo.tznamecCsF|jrd}nd}|jtkrd|j|j|j|fSd|j|j|j|fS)NDSTSTDzz)rHr+r8r$r,)r&r9rrrr@s zDstTzInfo.__repr__cCs"tj|jt|jt|j|jffSr")rArBr$rr+rHr,r%rrrrCs zDstTzInfo.__reduce__)NNrDr")r(r)r*rErPrIr$rGrHrMr3r?r<r6r9r:r@rCrrrrrFs"   7  '& rFcCst|}|dur |St|}t|}z |j|||fWSty%Ynw|jD]}|j|kr;|j|kr;|Sq+|||f}|||j|j|<|j|S)a%Factory function for unpickling pytz tzinfo instances. This is shared for both StaticTzInfo and DstTzInfo instances, because database changes could cause a zones implementation to switch between these two base classes and we can't break pickles on a pytz version upgrade. N) rAtimezonerrGr valuesr+rHrJ)r$r6 dstoffsetr:tz localized_tzrLrrr unpicklers$      ro)NNN)rErrrbisectrr[ NameErrorsetsrrApytz.exceptionsrr__all__r rutcfromtimestamprrrrrr8rr r-rFrorrrrs4      Pw