Lint workflow for python import reordering

[jamesobutler]

This closes #6272 by use of https://github.com/asottile/reorder_python_imports. It's style is similar to black philosophy of trying to reduce merge conflicts (https://github.com/asottile/reorder_python_imports#why-this-style).

Note that the original describes a solution using flake8-import-order, but upon reviewing the repo https://github.com/PyCQA/flake8-import-order and specifically https://github.com/PyCQA/flake8-import-order/issues/163, there appears to be discussion about archiving the project or letting someone else take it over. Due to this uncertainty I went with https://github.com/asottile/reorder_python_imports which was mentioned as a python reordering hooks at https://pre-commit.com/hooks.html.

This style is not conforming to the current (see below) such as one package per line with multiple functions allowed. Something to consider.

Slicer/Docs/developer_guide/style_guide.md

Lines 31 to 37 in 0346b3b

	- Imports
	- Grouped in order of scope/commonallity
	- Standard library imports
	- Related third party imports
	- Local apps/library specific imports
	- Slicer application imports and local/module imports may be grouped independently.
	- One package per line (with or without multiple function/module/class imports from the package)

Once merged STYLE: Apply reorder-python-imports changes could be a good candidate for inclusion in https://github.com/Slicer/Slicer/blob/main/.git-blame-ignore-revs.

[jamesobutler]

Still need to test locally to confirm that any order changing hasn't broken anything.

[jcfr]

Thanks for working on this 🙏 Having a way to systematically enforce the orders makes sense.

Alphabetical re-ordering within a group of imports makes sense.

That said, I am wondering is there is a way to configure the tool to:

• keep the grouping stdlib/package/Slicer
• keep the from package import (a, b, c) across multiple lines without changing it to from package import a, ...

I will further review on Monday when back.

[jamesobutler]

Some issues seemingly going on related to SegmentStatistics ordering

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "C:\S5R\python-install\Lib\imp.py", line 169, in load_source
    module = _exec(spec, sys.modules[name])
  File "<frozen importlib._bootstrap>", line 613, in _exec
  File "<frozen importlib._bootstrap_external>", line 850, in exec_module
  File "<frozen importlib._bootstrap>", line 228, in _call_with_frames_removed
  File "C:/S5R/Slicer-build/lib/Slicer-5.1/qt-scripted-modules/SegmentStatistics.py", line 7, in <module>
    from SegmentStatisticsPlugins import *
  File "C:\S5R\Slicer-build\lib\Slicer-5.1\qt-scripted-modules\SegmentStatisticsPlugins\__init__.py", line 1, in <module>
    from .ClosedSurfaceSegmentStatisticsPlugin import *
  File "C:\S5R\Slicer-build\lib\Slicer-5.1\qt-scripted-modules\SegmentStatisticsPlugins\ClosedSurfaceSegmentStatisticsPlugin.py", line 6, in <module>
    class ClosedSurfaceSegmentStatisticsPlugin(SegmentStatisticsPluginBase):
TypeError: module() takes at most 2 arguments (3 given)
loadSourceAsModule - Failed to load file "C:/S5R/Slicer-build/lib/Slicer-5.1/qt-scripted-modules/SegmentStatistics.py"  as module "SegmentStatistics" !
Fail to instantiate module  "SegmentStatistics"

[jamesobutler]

Some issues seemingly go on related to ordering

Traceback (most recent call last):
  File "C:\S5R\Slicer-build\lib\Slicer-5.1\qt-scripted-modules\SegmentEditorEffects\SegmentEditorThresholdEffect.py", line 40, in __init__
    self.setupPreviewDisplay()
  File "C:\S5R\Slicer-build\lib\Slicer-5.1\qt-scripted-modules\SegmentEditorEffects\SegmentEditorThresholdEffect.py", line 648, in setupPreviewDisplay
    if not self.scriptedEffect.segmentationDisplayableInView(sliceWidget.mrmlSliceNode()):
TypeError: method requires a VTK object
qSlicerPythonCppAPI::instantiateClass  - [ "SegmentEditorThresholdEffect" ] - Failed to instantiate scripted pythonqt class "SegmentEditorThresholdEffect" 0x23b3d977090

[jamesobutler]

This ordering issue is likely what was described in the following comment:

#6484 (comment)

you need to import vtk before you instantiate VTK-based classes.

[jamesobutler]

Some issues seemingly going on related to ordering for DataProbe

Traceback (most recent call last):
  File "C:/S5R/Slicer-build/lib/Slicer-5.1/qt-scripted-modules/DataProbe.py", line 55, in addView
    self.infoWidget = DataProbeInfoWidget(parent)
  File "C:/S5R/Slicer-build/lib/Slicer-5.1/qt-scripted-modules/DataProbe.py", line 94, in __init__
    self._createSmall()
  File "C:/S5R/Slicer-build/lib/Slicer-5.1/qt-scripted-modules/DataProbe.py", line 402, in _createSmall
    self.sliceAnnotations = DataProbeLib.SliceAnnotations()
  File "C:\S5R\Slicer-build\lib\Slicer-5.1\qt-scripted-modules\DataProbeLib\SliceViewAnnotations.py", line 24, in __init__
    self.dataProbeUtil = DataProbeUtil.DataProbeUtil()
AttributeError: type object 'DataProbeUtil' has no attribute 'DataProbeUtil'

[jcfr]

Re: ordering issue

These issues seem familiar, looking at the history of some of the script may give insight as I encountered similar ones in the past.

[jamesobutler]

Closing stale PR. Can use as reference for future work towards closing the related issue.