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Python DateTime does not match format when use the function inside celery task

I create a function to get the different between two date time and its working fine, But when i use it in celery it returns the following error:
ValueError: time data '2023-02-16T14:38:33.301574' does not match format '%Y-%m-%d %H:%M:%S.%f'
Any advice please

I recommend not doing this. Python standard library gives you everything you need to deal with ISO 8601 formatted date/time data. I advise you to use datetime.datetime.fromisoformat and datetime.datetime.isoformat instead.

Trying to convert influxdb timestamp in a csv to date and time columns

I am migrating an InfluxDB database to mySQL. I have managed to export the influx data to a CSV file, which is great, but now I am stuck with the date and time field which has been given to me.
I have no idea what format it is in, after doing some research it tells me that it is in epoch time, but using python to try and convert the timestamp to an ISO format, it isn't recognised as a valid timestamp. Any idea how to get this converted. Ideally to separate date and time columns. The data that I have got is something like this :
time,absoluteHumidity
1578152602608558363,5.788981747966442
1578152608059500073,4.769760557208695
1578152613662193439,5.788981747966442
And the python that I was using to try and convert it, was this :
from datetime import datetime, timezone
print (datetime.fromtimestamp(1578152602608558363, timezone.utc))
Any help or suggestions would be appreciated !

According to the influxdb docs they store timestamp values with nanoseconds precision.
However the datetime.fromtimestamp method expects a floating point number and its integer part is in second precision.
So generally your approach is right you just need to divide the influx timestamp by 1e9 and it should just work:
from datetime import datetime, timezone
print(datetime.fromtimestamp(1578152602608558363 / 1e9, timezone.utc))

Formatting datetime pandas

I have some rows in my dataset with the following release date format:
1995-10-30
It is an object/string. However, I want to convert it to datetime, so I wrote the following to achieve that:
movies_df["release_date"] = pd.to_datetime(movies_df.release_date)
It gets converted to datetime as it should, but I would like to have the following format
mm-dd-year
I have tried yearfirst=False and dayfirst=False but nothing seems to be happening and I cant figure out why it isnt working.
I have also tried to specify the format in the to_datetime method as following:
movies_df["release_date"] = pd.to_datetime(movies_df.release_date, format="%Y/%m/%d", dayfirst=False, yearfirst=False)
Any help is appriciated

You can convert datetimes to strings with format mm-dd-YY:
movies_df["release_date"] = pd.to_datetime(movies_df.release_date).dt.strftime('%m-%d-%Y')
But if want datetimes in format mm-dd-YY it is not possible in python.

Converting timestamp to unix date python

Here is how the timestamp looks -
2015-07-17 06:01:51.066141+00:00
I'm looking around to convert this to unix date time.
datetime.strptime("2015-07-17 06:01:51.066141+00:00", "%Y-%m-%d %H:%M:%S.%f%z").strftime("%s")
ValueError: 'z' is a bad directive in format '%Y-%m-%d %H:%M:%S.%f%z'
throws error for me, probably because of wrong format being used.
PS: my virtualenv is on python 2.7
ideas please ?

python 2.7 strptime() does not support z directive, either you can use python 3.2+ or some other 3rd party library like dateutil.

For Python 2.7 use arrow:
import arrow
date_str = "2015-07-17 06:01:51.066141+00:00"
unix_time = arrow.get(date_str).timestamp
On PY3 (verified on 3.4), using only standard libs
The date string you show will not be parsed by the standard python datetime library since it has a colon in the timezone (see here). The colon can be easily removed since it's always in the same position (or use rfind to find its index starting from the right). Your simplest solution is:
import datetime
date_str = "2015-07-17 06:01:51.066141+00:00"
date_str_no_colon = date_str[:-3]+date_str[-2:] # remove last colon
dt_obj = datetime.datetime.strptime(date_str_no_colon, "%Y-%m-%d %H:%M:%S.%f%z")
unix_time = dt_obj.timestamp()
Note that arrow should still work with PY3, and is a better solution in general- you don't want to get into datetime parsing wars with python. It will win.

The way to parse the date is not right. You'll either need to parse it by hand, find another library (for example the dateutil.parser.parse method that will parse your string directly without supplying format string) that supports that format or make the timestamp in another format. Even with newer versions of python the %z directive does not accept TZ offsets in the +/-HH:MM format (with colon).
As the source of the timestamp is django.DateTimeField maybe this question can help?
For converting to unix timestamp you seem to have to do some work since there does not seem to be a direct method for that:
(t - datetime.utcfromtimestamp(0)).total_seconds()
where t is the datetime (assuming it's in UTC and there is no tzinfo) you want to convert to POSIX timestamp. If the assumption is not correct you need to put tzinfo in the zero timestamp you subtract as shown below where the assumption does not hold.
If you want to use dateutil.parser the complete solution would be:
(dateutil.parser.parse(timestamp) - datetime.utcfromtimestamp(0).replace(tzinfo=utc()).total_seconds()

strptime() has no support for timezones.
So, you can make the conversion ignoring the timezone in the following way:
datetime.strptime("2015-07-17 06:01:51.066141", "%Y-%m-%d %I:%M:%S.%f").strftime("%s")
'1437102111'
Or in order to avoid using %s, as suggested below in the commments :
from datetime import datetime
(datetime.strptime("2015-07-17 06:01:51.066141", "%Y-%m-%d %I:%M:%S.%f") - datetime(1970, 1, 1)).total_seconds()
1437112911.066141
Notice this is a working version for Python 2, you can also check solutions for other versions here
Otherwise, you will have to use other libraries (django.utils or email.utils) that support timezones, or implement the timezone parsing on your own.
P.S. :
strptime docs appear to have support for timezone, but in fact it has not been implemented. Try :
datetime.strptime("2015-07-17 06:01:51.066141+00:00", "%Y-%m-%d %I:%M:%S.%f%z").strftime("%s")
and you will see that it is not supported. You can also verify it by searching more about strptime()

There are two parts:
to convert "2015-07-17 06:01:51.066141+00:00" into a datetime object that represents UTC time, see Convert timestamps with offset to datetime obj using strptime. Or If you know that the utc offset is always +0000:
from datetime import datetime
utc_time = datetime.strptime(time_string, "%Y-%m-%d %H:%M:%S.%f+00:00")
to convert the UTC time to POSIX timestamp (unix time), see Converting datetime.date to UTC timestamp in Python:
from datetime import datetime
timestamp = (utc_time - datetime(1970, 1, 1)).total_seconds()

how to convert and subtract dates, times in python

I have the following date/time:
2011-09-27 13:42:16
I need to convert it to:
9/27/2011 13:42:16
I also need to be able to subtract one date from another and get the result in HH:MM:SS format. I have tried to use the dateutil.parser.parse function, and it parses the date fine but sadly it doesn't seem to get the time correctly. I also tried to use another method I found on stackoverflow that uses "time", but I get an error that time is not defined.

You can use datetime's strptime function:
from datetime import datetime
date = '2011-09-27 13:42:16'
result = datetime.strptime(date, '%Y-%m-%d %H:%M:%S')
You were lucky, as I had that above line written for a project of mine.
To print it back out, try strftime:
print result.strftime('%m/%d/%Y %H:%M:%S')

Use python-dateutil:
import dateutil.parser as dateparser
mydate = dateparser.parse("2011-09-27 13:42:16",fuzzy=True)
print(mydate.strftime('%m/%d/%Y T%H:%M:%S'))

http://docs.python.org/library/datetime.html#datetime.datetime.strptime
and
http://docs.python.org/library/datetime.html#datetime.datetime.strftime
(And the rest of the datetime module.)