Consistent date time object

[schloerke]

I think the changelog should mention that this is a potentially breaking change, since the returned object is different, and the string formatting is different.

now = datetime.utcnow().timestamp()

y = datetime.utcfromtimestamp(now)
y
#> datetime.datetime(2024, 2, 21, 5, 37, 58, 761000)
print(y)
#> 2024-02-21 05:37:58.761000

x = datetime.fromtimestamp(now, timezone.utc)
x
#> datetime.datetime(2024, 2, 21, 5, 37, 58, 761000, tzinfo=datetime.timezone.utc)
print(x)
# 2024-02-21 05:37:58.761000+00:00

Originally posted by @wch in #1142 (comment)

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The returned value should have the same original print method and eject. However, we should not use the deprecated methods.