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 behaviour of datetime.datetime.utcnow() returning UTC time as naive datetime object is obviously problematic and must be fixed. It can lead to unexpected result if your system local timezone is not UTC, since datetime library presume naive datetime object to represent system local time. For example, datetime.datetime.utcnow().timestaamp() gives timestamp of 4 hours ahead from correct value on my computer. Also, as of python 3.6, datetime.astimezone() can be called on naive datetime instances, but datetime.datetime.utcnow().astimezone(any_timezone) gives wrong result unless your system local timezone is UTC.