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How can I make django model datetime field data of midnight and timezone aware?

I am trying to set expire_time in my django model to be midnight of user's selected date with timezone aware. But I am not able to get it properly. Can anyone tell me how I can do it or where I am making mistake in my code?
My codes are,
date = datetime.strptime(str(request.POST.get('expire') + ', 23:59:59'),
'%Y-%m-%d, %H:%M:%S')
tz = timezone.get_current_timezone()
date_tz = tz.localize(date)
createEventInDB.ev_expire = date_tz
try:
createEventInDB.save()
except Exception as e:
error = e
So if I select date which is December 1st 2015, it would be posting as 2015-12-1
I want to save data in database like 2015-12-01 23:59:59. I want to give whole day to user. My current timezone is America/Chicago. I have set active timezone by ip. So I want to make it like user can post from anywhere but timezone must be UTC aware and expire at midnight. Can anyone tell me how can I make it possible?

based on the documentation at https://docs.djangoproject.com/en/1.8/topics/i18n/timezones/
When support for time zones is enabled, Django stores datetime information in UTC in the database, uses time-zone-aware datetime objects internally, and translates them to the end user’s time zone in templates and forms.
So all this is completely unnecessary and all you need to do is use the models.DateTimeField like you always did.
You can define a Date widget in the view or form and alter Time of DateTimeField later on to 23:59:59 before saving (or you can provide it as a default) and Django will automatically convert it to UTC before saving.

I want to do is 2015-12-01 23:59:59 utc
Your code in the question returns 23:59:59 in the current time zone.
It is even simpler to return "23:59:59 UTC" instead given the corresponding UTC date:
from datetime import datetime
import pytz
ev_expire = datetime(utc_date.year, utc_date.month, utc_date.day, 23, 59, 59,
tzinfo=pytz.utc)

How to remove the tzinfo completely from the time after converting to UTC in Python?

I came across this exact issue, and I can't figure out how to achieve the solution in my case.
Guido says
The solution is to remove the tzinfo completely from the time after
converting to UTC.
This is what I have tried:
date_time = parser.parse(i.pubDate.text)
news.publication_date = date_time.replace(tzinfo=None).date()
And I get the same error:
NotImplementedError: DatetimeProperty publication_date_time can only support UTC. Please derive a new Property to support alternative timezones.
So it seems I have to convert the date to UTC first. And here my research has failed me.
I came across this solution:
The solution suggested is this:
def date_time_to_utc(date_time):
tz = pytz.timezone('???')
return tz.normalize(tz.localize(date_time)).astimezone(pytz.utc)
But I don't have the timezone. I am scraping the date from a html source. So the timezone could really be from anywhere in the world. Is there no easy and reliable way to convert a date time to UTC?
I could use both dateutil and pytz to achieve this. Many Thanks.
UPDATE
It has been a really long day. I have misread the stack trace. However the question remains valid.
date_time = (datetime}2015-01-13 18:13:26+00:00
news.publication_date_time = date_time
This caused the crash. And it seems by doing this, I pass the unit test:
news.publication_date_time = date_time.replace(tzinfo=None)
Is this the correct way converting a GMT 0 datetime to UTC datetime? Or in fact any timezone to UTC?

Is this the correct way converting a GMT 0 datetime to UTC datetime? Or in fact any timezone to UTC?
If aware datetime object is already in UTC (+0000) then your formula works:
naive_utc = aware_utc.replace(tzinfo=None)
where aware_utc is a timezone-aware datetime object that represents time in UTC.
But if aware datetime object is not in UTC; it fails. You should take into account a (possibly) non-zero UTC offset in the general case:
assert aware.tzinfo is not None and aware.utcoffset() is not None
# local time = utc time + utc offset (by definition)
# -> utc = local - offset
naive_utc = aware.replace(tzinfo=None) - aware.utcoffset()
where aware is a timezone-aware datetime object in an arbitrary timezone.
But I don't have the timezone. I am scraping the date from a html
source. So the timezone could really be from anywhere in the world. Is
there no easy and reliable way to convert a date time to UTC? I could
use both dateutil and pytz to achieve this. Many Thanks.
No. dateutil, pytz won't help you unless the date string itself contains the timezone (or at least its utc offset).
Remember: It is always noon somewhere on Earth i.e., if you collect date/time strings from different places on Earth then you can't compare them unless you attach the corresponding timezones. You can't convert it to UTC, you can't get a valid POSIX timestamp if you don't know the source timezone for the date.

I'm an idiot and it's late here, this time I read the question.
tstmp= date_time.replace(tzinfo=utc).total_seconds()
naive_date = datetime.utcfromtimestamp(tstmp)
First answer will just give you the current naive time

Try this:
dateTime = dateTime.replace(tzinfo=None)
dtUtcAware = pytz.UTC.localize(dateTime)

Python - convert naive datetime to UTC

I have date that I get in specific timezone time, but system deals with it as UTC and later it converts it back in that timezone, messing time.
For example like this:
I get this time: 2014-05-05 10:50:30. its datetime object. It has no timezone info, but I can get timezone info from user that uses that time. The thing is this time is showed as 'Europe/Vilnius' time, but system deals with it as UTC and when it outputs time to user it adds +3 hours showing wrong time. It does not matter if I change timezone to users timezone on that datetime object, it still outputs with +3 hours.
For example (snippet of code):
from datetime import datetime
import pytz
create_date = datetime.strptime(stage_log.create_date, "%Y-%m-%d %H:%M:%S")
tz = pytz.timezone(self.user_id.tz)
create_date = create_date.replace(tzinfo=pytz.utc)
This does not do anything and I still get wrong time.
Is there a way to move time to be correct UTC time(so then system correctly convert to users timezone) like this:
2014-05-05 10:50:30 -> convert to UTC. If timezone is 'Europe/Vilnius', it should convert that time to 2014-05-05 07:50:30. Then when system automatically does conversions it would correctly display 2014-05-05 10:50:30, because thats the time it should display.
Also if there is a way to just get number of hours that given timezone differs from UTC, then I could just do as simple as that:
create_date.replace(hour=create_date.hour-timezone_difference)

While this question does not specifically reference odoo, hopefully the following may help others:
Odoo - convert datetime to UTC:
(note: in this example self.start_date is a fields.Date)
start_date = fields.Datetime.to_string(pytz.timezone(self.env.context['tz']).localize(fields.Datetime.from_string(self.start_date), is_dst=None).astimezone(pytz.utc))
similar but with +24 hrs
end_date = fields.Datetime.to_string(pytz.timezone(self.env.context['tz']).localize(fields.Datetime.from_string(self.end_date), is_dst=None).astimezone(pytz.utc) + timedelta(hours=24))
This was used because the passed values (self.start_date) were field.Date and therefor did not get affected by timezones, while the target stored fields were fields.Datetime and therefor stored in UTC.
start_date/end_date which are now in UTC can then be used in a self.env[''].search([])

Converting timezone in in Python (Django) adding a mysterious 30 minutes

I have a datetime object that is set to 2014-02-24 19:00:00+00:00 and I believe this is set as UTC by default (through the Django admin panel).
This time is actually Africa/Johannesburg, so I convert it like this:
local_timezone= pytz.timezone("Africa/Johannesburg")
local_time_start = self.start_time_unix.replace(tzinfo=local_timezone)
This will now output 2014-02-24 19:00:00+01:30
Now I want to store this as the converted UTC timezone, so I do it like this:
utc_time = local_time_start.astimezone(utc)
For some reason, this outputs 2014-02-24 17:30:00+00:00. The time is should output is 17:00:00 so where is the extra 30 mins coming from?
Basically I am trying to take the given input from the django admin panel as the local timezone of the models time_zone field, but store it as UTC.
Is there a better way I can approach this? The Django docs explain how to convert the users local timezone but I need to convert it based on the timezone in the models attributes.

Don't use datetime.replace() with pytz timezones. The pytz timezones contain historical timezone data (to allow for dates in the past to use the right offsets from UTC), but datetime.replace() cannot use the correct information in that case.
Use the timezone.localize() method instead:
local_timezone = pytz.timezone("Africa/Johannesburg")
local_time_start = local_timezone.localize(self.start_time_unix)
See the pytz documentation.
Use this only on non-timezone-aware objects. For timezone aware datetime values, use datetime.astimezone() to translate value from one timezone to another:
local_timezone = pytz.timezone("Africa/Johannesburg")
local_time_start = self.start_time_unix.astimezone(local_timezone)
If you have a datetime value that has the wrong timezone attached (it should represent the given time in a different timezone, not a different time in that timezone), remove the old timezone first using .replace(tzinfo=None), then usetimezone.localize()`:
local_timezone = pytz.timezone("Africa/Johannesburg")
local_time_start = local_timezone.localize(self.start_time_unix.replace(tzinfo=None))

How to get user's local timezone other than server timezone(UTC) in python?

In OpenERP, when I try to print the current date and time, it always print the 'UTC' time. But I want to get time in the user timezone . Each user have different timezone.For example 'CST6CDT', 'US/Pacific' or 'Asia/Calcutta'. So I need to get time in user timezone so that I can show the correct datetime in the report. I have tried to change the timezone using localize() and replace() function in datatime module. But I didn't get the correct output.

Got it.
from datetime import datetime
from pytz import timezone
fmt = "%Y-%m-%d %H:%M:%S"
# Current time in UTC
now_utc = datetime.now(timezone('UTC'))
print now_utc.strftime(fmt)
# Convert to US/Pacific time zone
now_pacific = now_utc.astimezone(timezone('US/Pacific'))
print now_pacific.strftime(fmt)
# Convert to Europe/Berlin time zone
now_berlin = now_pacific.astimezone(timezone('Europe/Berlin'))
print now_berlin.strftime(fmt)
Courtesy: http://www.saltycrane.com/blog/2009/05/converting-time-zones-datetime-objects-python/

As of OpenERP 6.1 the timezone of all Python operations happening on the server-side (and in modules) is forced to be UTC. This was a design decision explained in various places [1]. The rendering of datetime values in the user's timezone is meant to be done on the client-side exclusively.
There are very few cases where it makes sense to use the user's timezone instead of UTC on the server-side, but indeed printing datetime values inside reports is one of them, because the client-side will have no chance to convert the contents of the resulting report.
That's why the report engine provides a utility method for doing so: the formatLang() method that is provided in the context of reports (RML-based ones at least) will format the date according to the timezone of the user if you call it with a datetime value and with date_time=True (it uses the tz context variable passed in RPC calls and based on the user's timezone preferences)
You can find example of how this is used in the official addons, for example in the delivery module (l.171).
Have a look at the implementation of formatLang() if you want to know how it actually does the conversion.
[1]: See the OpenERP 6.1 release notes, this other question, as well as comment #4 on bug 918257 or bug 925361.

from: http://help.openerp.com/question/30906/how-to-get-users-timezone-for-python/
DATETIME_FORMAT = "%Y-%m-%d %H:%M:%S"
import pytz
from openerp import SUPERUSER_ID
# get user's timezone
user_pool = self.pool.get('res.users')
user = user_pool.browse(cr, SUPERUSER_ID, uid)
tz = pytz.timezone(user.context_tz) or pytz.utc
# get localized dates
localized_datetime = pytz.utc.localize(datetime.datetime.strptime(utc_datetime,DATETIME_FORMAT)).astimezone(tz)

DateInUTC = <~ Time variable to convert
To convert to user's timezone:
LocalizedDate = fields.datetime.context_timestamp(cr, uid, DateInUTC, context=context)
To remove the offset:
LocalizedDate = LocalizedDate.replace(tzinfo=None)