chqnge doctest #54

Job	Run time
windows (windows-latest, Windows cl x32, cl, ilink, cl, ~build_tests.bat, run_tests.bat, set MSVS...	48s
unix (macos-latest, MacOS clang++, x86_64-apple-darwin, clang, clang, $LIBRARY_PATH, clang++, bui...	10s
windows (windows-latest, Windows cl x32 cpp98 ts, cl, ilink, cl, ~build_tests.bat, run_tests.bat,...	1m 5s
windows (windows-latest, Windows cl x64, cl, ilink, cl, ~build_tests.bat, run_tests.bat, set MSVS...	34s
windows (windows-latest, Windows cl x64 cpp98 ts, cl, ilink, cl, ~build_tests.bat, run_tests.bat,...	34s
unix (ubuntu-latest, Ubuntu g++5, armv7-unknown-linux-musleabihf, arm-linux-gnueabihf-gcc-5, gcc-...	11s
unix (ubuntu-latest, Ubuntu g++ latest, x86_64-unknown-linux-musl, gcc, gcc, $LIBRARY_PATH, g++, ...	11s
unix (ubuntu-20.04, Ubuntu 20.04 g++3.4, gcc, gcc, g++-3.4, /usr/lib/x86_64-linux-gnu:$LIBRARY_PA...	24s
unix (ubuntu-20.04, Ubuntu 20.04 g++4.4, gcc, gcc, g++-4.4, $LIBRARY_PATH, build_tests.sh, run_te...	1m 59s
	5m 56s

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