Mypyc is broken on Python 3.12 beta 1 -- there are compile errors. Let's keep track of them here:

• no member named 'ob_digit' in 'struct _longobject'
• no member named 'ob_size' in 'struct _object'
• '_PyErr_ChainExceptions' is deprecated [-Werror,-Wdeprecated-declarations]
• no member named 'gi_code' in 'PyGenObject'