Example with boxes is throwing validation error

[aorumbayev]

Steps to replicate

1. Run tealish compile on https://github.com/tinymanorg/tealish/blob/main/examples/boxes_with_structs.tl
2. Observe:

Error: Pattern ((?P<names>([a-z_][a-zA-Z0-9_]*,?\s*)+) = (?P<expression>.*)$) does not match for Assignment for line "box<Item> item1 = CreateBox("a")"

Further notes

I believe the latest merge with boxes wasn't propagated to pypi - perhaps its somehow related as well or some bug in the regex itsefl