support for python 3.13

[csoneson]

Python 3.13 was just released - I made a branch (py313) to add this to the tested versions. At the moment, the tests fail - seems to be an issue with scikit-image/regionprops.

[mbstadler]

Thanks for identifying this issue - I can reproduce it locally. I guess we'll give it a bit of time to see if scikit-image/regionprops fixes this.

[csoneson]

Minimal example to trigger the error:

conda environment:

conda create -n skim_313 python=3.13
conda activate skim_313
pip install numpy scikit-image

This installs numpy 2.1.2, scikit-image 0.24.0. The following code:

import numpy as np
import skimage.measure as skim
msk = np.random.randint(0, 16, size=(4, 5))
props = skim.regionprops(msk)

gives the error:

Traceback (most recent call last):
  File "<python-input-1>", line 2, in <module>
    props = skim.regionprops(msk)
            ^^^^^^^^^^^^^^^^
  File ".../envs/skim_313/lib/python3.13/site-packages/lazy_loader/__init__.py", line 82, in __getattr__
    submod = importlib.import_module(submod_path)
  File ".../envs/skim_313/lib/python3.13/importlib/__init__.py", line 88, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
           ~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "<frozen importlib._bootstrap>", line 1387, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1360, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1331, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 935, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 1022, in exec_module
  File "<frozen importlib._bootstrap>", line 488, in _call_with_frames_removed
  File ".../envs/skim_313/lib/python3.13/site-packages/skimage/measure/_regionprops.py", line 1426, in <module>
    _install_properties_docs()
    ~~~~~~~~~~~~~~~~~~~~~~~~^^
  File ".../envs/skim_313/lib/python3.13/site-packages/skimage/measure/_regionprops.py", line 1421, in _install_properties_docs
    getattr(RegionProperties, p).__doc__ = prop_doc[p]
                                           ~~~~~~~~^^^
KeyError: 'area_bbox'

With python 3.12.7 (everything else the same, including numpy and scikit-image versions), the error is not triggered.

[csoneson]

And in fact, if I install the scikit-image-0.25.0rc2.dev0 release candidate from GitHub, the error disappears 🎉.