Address incompatibility in syntax for data types

doc/tools/apigen.py

@@ -218,7 +218,7 @@ def _parse_module_with_import(self, uri):
                 continue
 
             # figure out if obj is a function or class
-            if isinstance(obj, FunctionType | BuiltinFunctionType):
+            if isinstance(obj, (FunctionType, BuiltinFunctionType)):
                 functions.append(obj_str)
             elif isinstance(obj, ModuleType) and 'skimage' in mod.__name__:
                 submodules.append(obj_str)

skimage/feature/_fisher_vector.py

@@ -99,7 +99,7 @@ def learn_gmm(descriptors, *, n_modes=32, gm_args=None):
             'order to use the Fisher vector functionality.'
         )
 
-    if not isinstance(descriptors, list | np.ndarray):
+    if not isinstance(descriptors, (list, np.ndarray)):
         raise DescriptorException(
             'Please ensure descriptors are either a NumPY array, '
             'or a list of NumPy arrays.'

skimage/filters/thresholding.py

@@ -313,7 +313,7 @@ def _validate_image_histogram(image, hist, nbins=None, normalize=False):
         raise Exception("Either image or hist must be provided.")
 
     if hist is not None:
-        if isinstance(hist, tuple | list):
+        if isinstance(hist, (tuple, list)):
             counts, bin_centers = hist
         else:
             counts = hist

skimage/io/collection.py

@@ -299,7 +299,7 @@ def __getitem__(self, n):
         if hasattr(n, '__index__'):
             n = n.__index__()
 
-        if not isinstance(n, int | slice):
+        if not isinstance(n, (int, slice)):
             raise TypeError('slicing must be with an int or slice object')
 
         if isinstance(n, int):

skimage/measure/fit.py

@@ -857,7 +857,7 @@ def ransac(
     rng = np.random.default_rng(rng)
 
     # in case data is not pair of input and output, male it like it
-    if not isinstance(data, tuple | list):
+    if not isinstance(data, (tuple, list)):
         data = (data,)
     num_samples = len(data[0])
 

skimage/segmentation/_watershed.py

@@ -67,7 +67,7 @@ def _validate_inputs(image, markers, mask, connectivity):
         markers_bool = local_minima(image, connectivity=connectivity) * mask
         footprint = ndi.generate_binary_structure(markers_bool.ndim, connectivity)
         markers = ndi.label(markers_bool, structure=footprint)[0]
-    elif not isinstance(markers, np.ndarray | list | tuple):
+    elif not isinstance(markers, (np.ndarray, list, tuple)):
         # not array-like, assume int
         # given int, assume that number of markers *within mask*.
         markers = regular_seeds(image.shape, int(markers / (n_pixels / image.size)))

skimage/transform/tests/test_geometric.py

@@ -747,10 +747,11 @@ def test_inverse_all_transforms(tform):
     assert_almost_equal(tform.inverse.inverse(SRC), tform(SRC))
     # Test addition with inverse, not implemented for all
     if not isinstance(
-        tform,
-        EssentialMatrixTransform
-        | FundamentalMatrixTransform
-        | PiecewiseAffineTransform,
+        tform, (
+            EssentialMatrixTransform,
+            FundamentalMatrixTransform,
+            PiecewiseAffineTransform,
+        )
     ):
         assert_almost_equal((tform + tform.inverse)(SRC), SRC)
         assert_almost_equal((tform.inverse + tform)(SRC), SRC)