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## Description
This adds an API for getting the wall / attachable variant of a block.
Unlike #117 it does not add convenience methods for orientation, and it
does not modify the example to use this code.
## Test Plan
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The extractor is not tested.
The API has some tests in the test module.
#### Related
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fixes. -->
#115 - it does not fix this, as it doesn't modify the example, but it
could lead to it.
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Co-authored-by: EmperialDev <saroke.dev@gmail.com>
