Why does datetime.datetime.utcnow() not contain timezone information?

Question

datetime.datetime.utcnow()

Why does this datetime not have any timezone info given that it is explicitly a UTC datetime?<

Answer 1

The standard Python libraries don't include any tzinfo classes (but see pep 431). I can only guess at the reasons. Personally I think it was a mistake not to include a tzinfo class for UTC, because that one is uncontroversial enough to have a standard implementation.

Edit: Although there's no implementation in the library, there is one given as an example in the tzinfo documentation.

from datetime import timedelta, tzinfo

ZERO = timedelta(0)

# A UTC class.

class UTC(tzinfo):
    """UTC"""

    def utcoffset(self, dt):
        return ZERO

    def tzname(self, dt):
        return "UTC"

    def dst(self, dt):
        return ZERO

utc = UTC()

To use it, to get the current time as an aware datetime object:

from datetime import datetime 

now = datetime.now(utc)

There is datetime.timezone.utc in Python 3.2+:

from datetime import datetime, timezone 

now = datetime.now(timezone.utc)