Description

Timmmm

opened on Jan 27, 2026

Issue body actions

Bug report

Bug description:

This code runs fine on Python 3.13.7:

import xml.etree.ElementTree as ET
x = ET.Element("x")
ET.SubElement(x, 0, parent="0")

However, Pyright correctly detects a type error in the SubElement call. SubElement has this Python signature:

def SubElement(parent, tag, attrib={}, **extra):

The parent parameter has already been assigned, so this should fail. I believe the fact that it doesn't is because it's actually using a C implementation, and the C implementation has this type signature:

def SubElement(parent, tag, /, attrib={}, **extra):

Which does allow specifying parent="0".

So I think the solution is just to add that / into the Python code.

CPython versions tested on:

3.13

Operating systems tested on:

Linux

Linked PRs

• gh-144270: Fix xml.etree.ElementTree.SubElement signature inconsistency #144313
• gh-144270: make SubElement parent and tag positional-only #144845

Activity

1. Timmmm

   added

   type-bugAn unexpected behavior, bug, or errorAn unexpected behavior, bug, or error

   on Jan 27, 2026
2. aisk

   added

   topic-XML

   on Jan 27, 2026
3. python

   deleted a comment from abdulaziz4alanazi4-spec on Jan 27, 2026
4. StanFromIreland

   added

   stdlibStandard Library Python modules in the Lib/ directoryStandard Library Python modules in the Lib/ directory

   on Jan 27, 2026
5. serhiy-storchaka commented on Feb 4, 2026

   

   serhiy-storchaka

   on Feb 4, 2026

   Member

   More actions

   @Timmmm, your idea looks good to me. Are you interesting in creating a PR?

   Reacted by Tim Hutt
6. NekoAsakura

   added 3 commits that reference this issue on Feb 15, 2026

   pythongh-144270: make SubElement parent and tag positional-only

   d956c30

   pythongh-144270: make SubElement parent and tag positional-only

   1551ff7

   pythongh-144270: make Element and SubElement parameters positional-only

   38af9cf
7. NekoAsakura

   added a commit that references this issue on Mar 30, 2026

   Merge remote-tracking branch 'upstream/main' into pythongh-144270-sub…

   6f43dc8
8. serhiy-storchaka

   added a commit that references this issue on Mar 30, 2026

   gh-144270: Make SubElement parent and tag positional-only (GH-144845)

   afd8113
9. serhiy-storchaka

   closed this as completedon Mar 30, 2026
10. maurycy

    added a commit that references this issue on Mar 30, 2026

    Merge remote-tracking branch 'upstream/main' into tachyon-ndjson-kole…

    6a0ea81
11. clin1234

    added a commit that references this issue on Apr 16, 2026

    pythongh-144270: Make SubElement parent and tag positional-only (pyth…

    badd7fd
12. ljfp

    added a commit that references this issue on Apr 25, 2026

    pythongh-144270: Make SubElement parent and tag positional-only (pyth…

    cbeb824

Issue actions