build(deps): update tzdata requirement from >=2026.4 to >=2026.5 in /clients/py

[dependabot]

Updates the requirements on tzdata to permit the latest version.

Release notes

Sourced from tzdata's releases.

2026.5: Release of upstream tzdata 2026e

Version 2026.5

Upstream version 2026e released 2026-09-30T00:14:38+00:00.

Briefly:

Manitoba moves to permanent -05 on 2026-10-31.

Changes to future timestamps

Manitoba’s 2026-03-08 spring forward was its last foreseeable clock change, as it moved to permanent -05 thereafter. Model this with its traditional abbreviation EST. Although the change to permanent -05 legally takes place on 2026-10-31, temporarily model the change to occur on 2026-11-01 at 02:00 for the same reason as other recent temporary hacks. (Caution: see “NOTE FOR 2026b TEMPORARY HACK FOR CLDR AND CANADA” below.)

As the change affects both America/Winnipeg and its backward compatibility link, the obsolescent setting TZ="Canada/Central" will now use the abbreviation EST for affected timestamps, akin to TZ="Canada/Pacific" behavior introduced in 2026b.

Another TZDB release may be needed soon if any of the portions of northwestern Ontario historically aligned with America/Winnipeg do not follow. For now, given the short leadtime with Manitoba’s announcement, assume that they will, to avoid creating new zones that may not be needed if no divergence occurs.

Changes to past timestamps

In 1925 Ireland fell back on 09-20 not 10-04 (thanks to Stan Ulbrych).

Changes to commentary

Discussion on timekeeping practices in northwestern Ontario has been expanded in light of Manitoba’s recent announcement. It is not yet known whether or to what extent these areas may adapt their own timekeeping practices in response.

Changelog

Sourced from tzdata's changelog.

Version 2026.5

Upstream version 2026e released 2026-09-30T00:14:38+00:00

Briefly:

Manitoba moves to permanent -05 on 2026-10-31.

Changes to future timestamps

Manitoba’s 2026-03-08 spring forward was its last foreseeable clock change, as it moved to permanent -05 thereafter. Model this with its traditional abbreviation EST. Although the change to permanent -05 legally takes place on 2026-10-31, temporarily model the change to occur on 2026-11-01 at 02:00 for the same reason as other recent temporary hacks. (Caution: see “NOTE FOR 2026b TEMPORARY HACK FOR CLDR AND CANADA” below.)

As the change affects both America/Winnipeg and its backward compatibility link, the obsolescent setting TZ="Canada/Central" will now use the abbreviation EST for affected timestamps, akin to TZ="Canada/Pacific" behavior introduced in 2026b.

Another TZDB release may be needed soon if any of the portions of northwestern Ontario historically aligned with America/Winnipeg do not follow. For now, given the short leadtime with Manitoba’s announcement, assume that they will, to avoid creating new zones that may not be needed if no divergence occurs.

Changes to past timestamps

In 1925 Ireland fell back on 09-20 not 10-04 (thanks to Stan Ulbrych).

Changes to commentary

Discussion on timekeeping practices in northwestern Ontario has been expanded in light of Manitoba’s recent announcement. It is not yet known whether or to what extent these areas may adapt their own timekeeping practices in response.

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Version 2026.4

Upstream version 2026d released 2026-09-11T22:21:07+00:00

Briefly:

Canada’s Northwest Territories moved to permanent -06 on 2026-08-21. Obsolescent settings like TZ="EST5EDT" now conform better to POSIX. Fix security, performance and porting bugs in zic and localtime.

Changes to future timestamps

Canada’s Northwest Territories will not fall back on 2026-11-01 and will stay on

... (truncated)

Commits

• 9493aab Update tzdata to version 2026e (#154)
• See full diff in compare view