mypy

gh-85943: Fix BytesWarning in the struct format cache under -bb (GH-1… #22527

Job	Run time
Run mypy on Tools/check-c-api-docs	33s
Run mypy on Lib/_pyrepl	33s
Run mypy on Tools/jit	33s
Run mypy on Lib/tomllib	32s
Run mypy on Tools/cases_generator	33s
Run mypy on Tools/peg_generator	32s
Run mypy on Tools/build	31s
Run mypy on Tools/clinic	33s
Run mypy on Lib/test/libregrtest	36s
	4m 56s

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