Matt McCormick

The `itk.elastix_registration_method` function is automatically generated from the `itk::ElastixRegistrationMethod` class. Indexed input's and output's to that class become the position `args`. The `Set*` methods become the `kwargs` (also supporting snake_case)....

E.g. https://github.com/InsightSoftwareConsortium/ITK/blob/9ff84420e55d2f86984f40f14861bddf0812b82b/Wrapping/Generators/Python/PyBase/pyBase.i#L280-L354

@ViktorvdValk to reproduce the error, uncomment: https://github.com/InsightSoftwareConsortium/ITKElastix/blob/30d2e9d9afacc25876fa5fc84842bae7d783cf6e/wrapping/test/itkTransformixFilterTest.py#L51-L53

@ViktorvdValk interesting.. could a PR please be created to enable the test in CI, please?

@N-Dekker has this been addressed with elastix 0.16.0?

We can do this [by defining `__contains__`](https://docs.python.org/3/reference/datamodel.html#object.__contains__).

@stefanklein @mstaring @N-Dekker are `itk::IterationEvent`'s emitted on iteration (or can we add this?) and emit this from the `itk::ElastixRegistrationMethod` class?

Depends on https://github.com/InsightSoftwareConsortium/ITKIOOMEZarrNGFF/issues/25

@aylward @hjmjohnson

Once Elastix has more complete itk::Transform support (in memory Python interface support via itk-elastix), this package will enable an elegant interface with MONAI: https://github.com/InsightSoftwareConsortium/itk-torch-transform-bridge