```cmake
set( DOCUMENTATION "This module contains ImageIO classes for reading microscopy
images (mostly TIFF based) readable by the OpenSlide library,
http://openslide.org.")

itk_module( IOOpenSlide
  DEPENDS
    ITKIOImageBase
  TEST_DEPENDS
    ITKTestKernel
  ENABLE_SHARED
  DESCRIPTION
    "${DOCUMENTATION}"
  EXCLUDE_FROM_DEFAULT
)
```

Add FACTORY_NAMES parameter to itk_module() declaration
user
```cmake
set( DOCUMENTATION "This module contains ImageIO classes for reading microscopy
images (mostly TIFF based) readable by the OpenSlide library,
http://openslide.org.")

itk_module( IOOpenSlide
  DEPENDS
    ITKIOImageBase
  TEST_DEPENDS
    ITKTestKernel
  ENABLE_SHARED
  FACTORY_NAMES
    ImageIO::OpenSlide
  DESCRIPTION
    "${DOCUMENTATION}"
  EXCLUDE_FROM_DEFAULT
)
```
assistant