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call-datetime-utcfromtimestamp (DTZ004)

Derived from the flake8-datetimez linter.

What it does

Checks for usage of datetime.datetime.utcfromtimestamp().

Why is this bad?

Python datetime objects can be naive or timezone-aware. While an aware object represents a specific moment in time, a naive object does not contain enough information to unambiguously locate itself relative to other datetime objects. Since this can lead to errors, it is recommended to always use timezone-aware objects.

datetime.datetime.utcfromtimestamp() returns a naive datetime object; instead, use datetime.datetime.fromtimestamp(ts, tz=...) to create a timezone-aware object.

Example

import datetime

datetime.datetime.utcfromtimestamp(946684800)

Use instead:

import datetime

datetime.datetime.fromtimestamp(946684800, tz=datetime.timezone.utc)

Or, on Python 3.11 and later:

import datetime

datetime.datetime.fromtimestamp(946684800, tz=datetime.UTC)

References