code: func (a *appScanner) MustExpandPackagePath(packagePath string) string {
  	pkgRealpath := swag.FindInGoSearchPath(packagePath)
  	if pkgRealpath == "" {
  		log.Fatalf("Can't find package %s \n", packagePath)
  	}
  
  	return pkgRealpath
  }
docs: // MustExpandPackagePath gets the real package path on disk