mypy

gh-71019: document which objects connect_read_pipe/connect_write_pipe… #22495

Job	Run time
Run mypy on Tools/build	31s
Run mypy on Tools/jit	32s
Run mypy on Tools/check-c-api-docs	35s
Run mypy on Lib/test/libregrtest	34s
Run mypy on Lib/_pyrepl	36s
Run mypy on Tools/clinic	30s
Run mypy on Tools/cases_generator	29s
Run mypy on Lib/tomllib	29s
Run mypy on Tools/peg_generator	31s
	4m 47s

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