Bug report

Bug description:

A calendar module CLI displays month names in a Polish, and other Slavic languages using the genitive case, as it is used in a phrase "in January". However, for standalone usage, month names should appear in the nominative case to be grammatically correct. For instance, in Polish, "January" should be written as "styczeń" instead of "stycznia"; similarly, in Russian, it should be "январь" rather than "января". This issue likely affects Baltic languages and Greek as well.

Example command demonstrating the issue:

python3 -m calendar --locale pl_PL --encoding utf

This problem occurs because the calendar module uses the strftime %B format specifier, which returns month names suitable for complete date contexts (genitive case). Instead, a nominative form is required when months are mentioned independently:

CPython versions tested on:

CPython main branch

Operating systems tested on:

macOS

Linked PRs

• gh-131146: Fix month names in a genitive case in calendar module #131147