mypy

gh-148406: Fix annotations of _colorize.FancyCompleter #20632

Job	Run time
Run mypy on Tools/jit	16s
Run mypy on Tools/cases_generator	17s
Run mypy on Lib/test/libregrtest	18s
Run mypy on Lib/tomllib	15s
Run mypy on Tools/build	18s
Run mypy on Tools/check-c-api-docs	16s
Run mypy on Lib/_pyrepl	18s
Run mypy on Tools/peg_generator	16s
Run mypy on Tools/clinic	18s
	2m 32s

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