func GetCommandLine() *FlagSet {
	return CommandLine
}
GetCommandLine returns the default FlagSet.
package pflag
import (
	"io/ioutil"
	"os"
)
func ResetForTesting(usage func()) {
	CommandLine = &FlagSet{
		name:          os.Args[0],
		errorHandling: ContinueOnError,
		output:        ioutil.Discard,
	}
	Usage = usage
}