hdiutil create -o /tmp/HighSierra.cdr -size 5130m -layout SPUD -fs HFS+J
hdiutil attach /tmp/HighSierra.cdr.dmg -noverify -mountpoint /Volumes/install_build
sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/install_build
mv /tmp/HighSierra.cdr.dmg ~/Desktop/InstallSystem.dmg
hdiutil convert /tmp/HighSierra.cdr.dmg -format UDTO -o /tmp/HighSierra.iso