mypy

gh-137829: Fix shelve tests for backend compatibility (#137879) #10232

Job	Run time
Run mypy on Lib/tomllib	17s
Run mypy on Tools/build	19s
Run mypy on Lib/test/libregrtest	18s
Run mypy on Tools/jit	19s
Run mypy on Tools/cases_generator	19s
Run mypy on Lib/_pyrepl	21s
Run mypy on Tools/clinic	18s
Run mypy on Tools/check-c-api-docs	17s
Run mypy on Tools/peg_generator	19s
	2m 47s

Provide feedback