Time conversions are generally a pain, especially when daylight savings time is involved. Here a number of libraries and tools to deal with this in Python. Firstly, there are three libraries
The datetime module supplies classes for manipulating dates and times in both simple and complex ways. While date and time arithmetic is supported, the focus of the implementation is on efficient attribute extraction for output formatting and manipulation. For related functionality, see also the time and calendar modules.
This module provides various time-related functions. For related functionality, see also the datetime and calendar modules.
This module allows you to output calendars like the Unix cal program, and provides additional useful functions related to the calendar.
London/Europepytz brings the Olson tz database into Python. This library allows accurate and cross platform timezone calculations using Python.
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from datetime import datetime as dt
import time as tm
import pytz as tz
import calendar as cal
The format definition is here. The result is either an object, or a timetuple struct, depending on the module.
dt.strptime(), tm.strptime(), [dt].timetuple()
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dto = dt.strptime ('2014-09-06 07:16 +0000', "%Y-%m-%d %H:%M %z")
dto
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tto = tm.strptime ('2014-09-06 07:16 +0000', "%Y-%m-%d %H:%M %z")
tto
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dto.timetuple() == tto
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dt.fromtimestamp(tm.mktime(tto))
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dto = dt.strptime('2014:09:13 21:07:15', '%Y:%m:%d %H:%M:%S')
timezone = tz.timezone('Europe/London')
dto = timezone.localize(dto)
dto
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epoch_time = 0
tm.gmtime(epoch_time)
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epoch_time = tm.time()
tm.gmtime(epoch_time)
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tm.gmtime(tm.mktime(tto))
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tm.time()
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dt.now()
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dt.now().strftime('%Y-%m-%d %H:%M:%S %Z%z')
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Depending on the library, strftime is either a function or a method. The format string is here
tm.strftime(), [dt].strftime()
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tm.strftime("%Y-%m-%d %H:%M",tto)
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dto.strftime("%Y-%m-%d %H:%M")
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dto.hour, dto.minute, dto.second,
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dto.tzname()
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from datetime import datetime as dt
import pytz as tz
def change_tz(datetime_obj, tz_str):
""" change the timezone
datatime_obj - a datetime.datetime object representing the time
tz_str - time zone string, eg 'Europe/London'
return - a datetime.datetime object
"""
the_tz = tz.timezone(tz_str)
the_dt = the_tz.normalize(datetime_obj.astimezone(the_tz))
return the_dt
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ams = tz.timezone('Europe/Amsterdam')
dto_ams = ams.normalize(dto.astimezone(ams))
dto_ams.strftime('%Y-%m-%d %H:%M:%S %Z%z')
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dto_ams2 = change_tz(dto, "Europe/Amsterdam")
dto_ams2
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dto_ams2.timetuple()
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