Fix a test case #5

Job	Run time
run-coverage (3.10, ubuntu-latest)	37s
run-coverage (3.10, macos-latest)	59s
run-coverage (3.10, windows-latest)	1m 20s
lint	23s
build-package	47s
unit-test (3.10, macos-latest)	1m 27s
unit-test (3.10, ubuntu-latest)	30s
unit-test (3.10, windows-latest)	1m 17s
unit-test (3.11, macos-latest)	49s
unit-test (3.11, ubuntu-latest)	28s
unit-test (3.11, windows-latest)	1m 22s
unit-test (3.7, macos-latest)	51s
unit-test (3.7, ubuntu-latest)	31s
unit-test (3.7, windows-latest)	1m 26s
unit-test (3.8, macos-latest)	52s
unit-test (3.8, ubuntu-latest)	33s
unit-test (3.8, windows-latest)	2m 29s
unit-test (3.9, macos-latest)	56s
unit-test (3.9, ubuntu-latest)	31s
unit-test (3.9, windows-latest)	1m 45s
unit-test (pypy-3.10, macos-latest)	2m 48s
unit-test (pypy-3.10, ubuntu-latest)	1m 47s
unit-test (pypy-3.10, windows-latest)	8m 51s
build-docs	31s
upload-coverage	9s
	33m 59s

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