Bug report

Bug description:

>>> datetime.fromisoformat('2020-01-01T00:00+00:90')
datetime.datetime(2020, 1, 1, 0, 0, tzinfo=datetime.timezone(datetime.timedelta(seconds=5400)))

expected result: ValueError (90 minutes is out of range 00-59)

I wasn't able to find a definitive paragraph of the ISO8601 to quote (it's not an open standard), but it appears datetime libraries in other languages (Temporal, NodaTime) do enforce this. Also, RFC3339 does explicitly forbid offset minutes outside the 00-59 range.

What are your thoughts?

CPython versions tested on:

3.13

Operating systems tested on:

macOS

Linked PRs

• gh-126883: Add check that timezone fields are in range for datetime.fromisoformat #127242