datetime - ISO time (ISO 8601) in Python

Question

I have a file. In Python, I would like to take its creation time, and convert it to an ISO time (ISO 8601) string while preserving the fact that it was created in the Eastern Time Zone (ET).

How do I take the file's ctime and convert it to an ISO time string that indicates the Eastern Time Zone (and takes into account daylight savings time, if necessary)?

Answer 1

Local to ISO 8601:

import datetime
datetime.datetime.now().isoformat()
>>> 2020-03-20T14:28:23.382748

UTC to ISO 8601:

import datetime
datetime.datetime.utcnow().isoformat()
>>> 2020-03-20T01:30:08.180856

Local to ISO 8601 without microsecond:

import datetime
datetime.datetime.now().replace(microsecond=0).isoformat()
>>> 2020-03-20T14:30:43

UTC to ISO 8601 with TimeZone information (Python 3):

import datetime
datetime.datetime.utcnow().replace(tzinfo=datetime.timezone.utc).isoformat()
>>> 2020-03-20T01:31:12.467113+00:00

UTC to ISO 8601 with Local TimeZone information without microsecond (Python 3):

import datetime
datetime.datetime.now().astimezone().replace(microsecond=0).isoformat()
>>> 2020-03-20T14:31:43+13:00

Local to ISO 8601 with TimeZone information (Python 3):

import datetime
datetime.datetime.now().astimezone().isoformat()
>>> 2020-03-20T14:32:16.458361+13:00

Notice there is a bug when using astimezone() on utc time. This gives an incorrect result:

datetime.datetime.utcnow().astimezone().isoformat() #Incorrect result

For Python 2, see and use pytz.