gh-153171: Produce specialized syntax errors for 'not' after an opera… #2376

Job	Run time
aarch64-unknown-linux-gnu/gcc	7m 0s
x86_64-unknown-linux-gnu/gcc-free-threading	8m 50s
x86_64-unknown-linux-gnu/gcc	10m 45s
aarch64-apple-darwin/clang	10m 13s
x86_64-apple-darwin/clang	15m 38s
	52m 26s

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