main.go
func addPath(paths []string, path string) []string {
	for _, existingpath := range paths {
		if path == existingpath {
			return paths
		}
	}
	return append(paths, path)
}
func addPath(paths []string, path string) []string {
	for _, existingpath := range paths {
		if path == existingpath {
			return paths
		}
	}
	return append(paths, path)
}
// addPath appends path to paths if path does not already exist in paths. Returns
// the new paths.