style(mahalanobis): drop unused import, fix isort drift

.claude/sweep-style-state.csv

@@ -11,6 +11,7 @@ geotiff,2026-06-25,,MEDIUM,4,"Re-sweep 2026-06-25 (file last modified 2026-06-24
 hydro-d8,2026-05-29,2705,HIGH,1;3;4,"flake8+isort over the 13 D8 files only (dinf/mfd out of scope). Cat 3 HIGH: F401 x2 (flow_length_d8 function-local _compute_accum_seeds never called; snap_pour_point_d8 module-level cuda_args unused) - both confirmed dead, no re-export. Cat 1: E127/E128 continuation-indent x90 (mostly multi-line def signatures); E302/E303 blank-line cluster in watershed_d8; E501 x4 (flow_path_d8 + snap_pour_point_d8, wrapped ternaries). Cat 4: isort import-block reordering on all 13 files. No Cat 2 (W-codes), no Cat 5 (grep clean: no bare except, mutable defaults, ==None/==True, or shadowed builtins). flake8+isort clean after fix; 385 D8 tests pass. flow_direction_d8 needed manual blank-line placement to satisfy both isort and E302."
 interpolate,2026-06-12,3286,HIGH,3;4,"Full subpackage sweep (_idw, _kriging, _spline, _validation). Cat 3 F401: unused 'import math' in _idw.py L5 (IDW kernels are pure arithmetic; _spline.py keeps math for math.log in TPS kernels; not re-exported, __init__ exports only idw/kriging/spline). Cat 4 isort: _idw.py + _spline.py 5-line xrspatial.utils from-import reflowed to 2 lines under line_length=100, matching _kriging.py from #2916. Cat 1/2/5 clean (no E/W codes; grep: no bare except, mutable defaults, ==None/True, shadowed builtins). flake8+isort clean after fix; 66 interpolation tests pass (CUDA available). PR open."
 interpolate-kriging,2026-06-04,2916,MEDIUM,1;4,"flake8 E128 x2: continuation-line under-indent at the _chunk_var kriging-predict calls in _kriging_dask_numpy (L234) and _kriging_dask_cupy (L324); re-indented to visual-indent column. Cat 4 isort: 5-line from xrspatial.utils (...) block collapses to one 88-char line under line_length=100. Cat 2/3/5 grep clean (no W-codes, F-codes, bare except, mutable defaults, ==None/True, or shadowed builtins). flake8+isort clean after fix; 14 kriging tests pass. PR open."
+mahalanobis,2026-06-30,,HIGH,3;4,F401 unused is_dask_cupy import (Cat 3 HIGH) + isort drift in xrspatial.utils block (Cat 4 MEDIUM); fixed in PR #3582; issue filing blocked by auto-mode external-write classifier
 mcda,2026-06-10,3143,HIGH,3;4,F401 dead function-local warnings import in standardize.py; isort drift in weights.py combine.py __init__.py; flake8 otherwise clean; Cat 5 greps clean; fixed via PR for #3143
 morphology,2026-06-20,3400,HIGH,3;4,"F401 xr/has_cuda_and_cupy/not_implemented_func + F841 size (dead); isort ordering. /rockout PR off issue 3400. flake8+isort clean, 74 tests pass."
 multispectral,2026-06-20,3428,HIGH,3;4,F401 unused not_implemented_func (Cat3 HIGH); isort dataset_support before utils (Cat4 MEDIUM); Cat1/2/5 clean; fixed via #3428

xrspatial/mahalanobis.py

@@ -13,16 +13,8 @@
 import numpy as np
 import xarray as xr
 
-from xrspatial.utils import (
-    ArrayTypeFunctionMapping,
-    _dask_task_name_kwargs,
-    _validate_raster,
-    has_cuda_and_cupy,
-    has_dask_array,
-    is_cupy_array,
-    is_dask_cupy,
-    validate_arrays,
-)
+from xrspatial.utils import (ArrayTypeFunctionMapping, _dask_task_name_kwargs, _validate_raster,
+                             has_cuda_and_cupy, has_dask_array, is_cupy_array, validate_arrays)
 
 try:
     import dask