https://qiita.com/temoki/items/e3c05ee7e0f7a37b87e9
brew install chathage echo 'github "SwiftyJSON/SwiftyJSON"' > Cartfile
carthage update --platform iOS --no-use-binaries *** Cloning SwiftyJSON *** Checking out SwiftyJSON at "5.0.1" *** xcodebuild output can be found in /var/folders/r1/2w1s0rtx4zlcfdwx5t764x4504bh74/T/carthage-xcodebuild.gCiWnX.logA shell task (/usr/bin/xcrun xcodebuild -workspace /Users/uu121543/Documents/xcode/CarthageTest/Carthage/Checkouts/SwiftyJSON/SwiftyJSON.xcworkspace CODE_SIGNING_REQUIRED=NO CODE_SIGN_IDENTITY= CARTHAGE=YES -list) failed with exit code 72:
xcrun: error: unable to find utility "xcodebuild", not a developer tool or in PATH
sudo xcode-select -switch /Applications/Xcode12.4.app/Contents/Developer/