code: func impPath(imp string) string {
  	if strings.HasPrefix(imp, "vendor/") {
  		imp = "/" + imp
  	}
  	if i := strings.LastIndex(imp, "/vendor/"); i != -1 {
  		imp = imp[i+len("/vendor/"):]
  	}
  	return imp
  }
docs: // impPath sanitizes the package path returned by `PkgPath` method of a reflect Type so that
  // it is importable. PkgPath might return a path that includes "vendor". These paths do not
  // compile, so we need to remove everything up to and including "/vendor/".
  // See https://github.com/golang/go/issues/12019.