`--fetch-missing-python` dies with "ValueError: too many values to unpack (expected 2)"

[cr1901]

Issue

I need functionality of a newer pipx than the 1.7.1 release from my distro provides; specifically, --fetch-missing-python doesn't work for that version anymore due to looking for SHA256 files in the old indygreg repo. As a workaround, I've tried using the zipapp. For several versions of pipx.pyz, I've gotten a "ValueError: too many values to unpack (expected 2)" when trying to use the --fetch-missing-python flag with a script containing inline script metadata. I've reproduced an MCVE below- I'm curious if this is "just on my machine" or not.

Environment

• OS: Linux Mint 21.3 Linux xubuntu-dtrain 5.15.0-170-generic #180-Ubuntu SMP Fri Jan 9 16:10:31 UTC 2026 x86_64 x86_64 x86_64 GNU/Linux
• Shell: bash
• Python version and path: /usr/bin/python3, Python 3.10.12
• pipx --version output: 1.11.0

The following commands should set up a clean directory to test:

pushd /tmp
mkdir pipx-test
cd pipx-test
wget https://github.com/pypa/pipx/releases/download/1.11.0/pipx.pyz
cat << EOF > download-sentinel.py
"""Create a script for generating Sentinel Verilog."""

# /// script
# requires-python = ">=3.11"
# dependencies = [
#    "sentinel @ git+https://github.com/cr1901/sentinel@next",
#    "amaranth[builtin-yosys]>=0.5.8",
# ]
# ///

import sentinel.gen

if __name__ == "__main__":
    sentinel.gen.cli()
EOF
python3 pipx.pyz run --verbose --no-cache --fetch-missing-python --python 3.12 download-sentinel.py --help

Output of the failing command

The last command above should set up a venv and print out a help text. However, instead it returns a ValueError.

william@xubuntu-dtrain:/tmp/pipx-test$ python3 pipx.pyz run --verbose --no-cache --fetch-missing-python --python 3.12 download-sentinel.py --help
pipx >(setup:1164): pipx version is 1.11.0
pipx >(setup:1165): Default python interpreter is '/usr/bin/python3.10'
pipx >(find_unix_command_python:74): Command `python3.12` was not found on the system
Traceback (most recent call last):
  File "/usr/lib/python3.10/runpy.py", line 196, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "/usr/lib/python3.10/runpy.py", line 86, in _run_code
    exec(code, run_globals)
  File "/tmp/pipx-test/pipx.pyz/__main__.py", line 3, in <module>
  File "/tmp/pipx-test/pipx.pyz/_bootstrap/__init__.py", line 262, in bootstrap
  File "/tmp/pipx-test/pipx.pyz/_bootstrap/__init__.py", line 38, in run
  File "/home/william/.shiv/pipx.pyz_2b49cbe47988522d7d908dc94f1e4fc11cd65e74411ae8da718ec4969024947c/site-packages/pipx/main.py", line 1230, in cli
    return run_pipx_command(parsed_pipx_args, subparsers)
  File "/home/william/.shiv/pipx.pyz_2b49cbe47988522d7d908dc94f1e4fc11cd65e74411ae8da718ec4969024947c/site-packages/pipx/main.py", line 268, in run_pipx_command
    interpreter = find_python_interpreter(
  File "/home/william/.shiv/pipx.pyz_2b49cbe47988522d7d908dc94f1e4fc11cd65e74411ae8da718ec4969024947c/site-packages/pipx/interpreter.py", line 105, in find_python_interpreter
    return download_python_build_standalone(python_version)
  File "/home/william/.shiv/pipx.pyz_2b49cbe47988522d7d908dc94f1e4fc11cd65e74411ae8da718ec4969024947c/site-packages/pipx/standalone_python.py", line 74, in download_python_build_standalone
    full_version, (download_link, digest) = resolve_python_version(python_version)
  File "/home/william/.shiv/pipx.pyz_2b49cbe47988522d7d908dc94f1e4fc11cd65e74411ae8da718ec4969024947c/site-packages/pipx/standalone_python.py", line 204, in resolve_python_version
    pythons = list_pythons()
  File "/home/william/.shiv/pipx.pyz_2b49cbe47988522d7d908dc94f1e4fc11cd65e74411ae8da718ec4969024947c/site-packages/pipx/standalone_python.py", line 173, in list_pythons
    available_python_links = [
  File "/home/william/.shiv/pipx.pyz_2b49cbe47988522d7d908dc94f1e4fc11cd65e74411ae8da718ec4969024947c/site-packages/pipx/standalone_python.py", line 177, in <listcomp>
    for link, digest in python_releases
ValueError: too many values to unpack (expected 2)

I've also tested the zipapps for 1.8.0, and 1.9.0, and get the same error.

[BillionClaw]

This is tracked in PR #1775 — the digest field from the GitHub API now includes a sha256: prefix that needs to be stripped before unpacking. Fix is in review.