added custom metric sample #637

Job	Run time
build-lint-test (3.9, ubuntu-latest)	13s
build-lint-test (3.9, macos-intel)	11s
build-lint-test (3.9, macos-arm)	11s
build-lint-test (3.9, windows-latest)	6s
build-lint-test (3.12, ubuntu-latest)	9s
build-lint-test (3.12, macos-intel)	11s
build-lint-test (3.12, macos-arm)	13s
build-lint-test (3.12, windows-latest)	9s
	1m 23s

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