Imports github.com/mitchellh/osext github.com/mitchellh/packer/packer github.com/mitchellh/packer/packer/plugin github.com/mitchellh/panicwrap github.com/mitchellh/prefixedio github.com/mitchellh/packer/command github.com/mitchellh/cli github.com/hashicorp/go-checkpoint Standard library imports io io/ioutil log os os/exec os/signal path/filepath runtime strings sync syscall bytes encoding/json errors fmt