code: func SanitizeURLKeepTrailingSlash(in string) string {
  	return sanitizeURLWithFlags(in, purell.FlagsSafe|purell.FlagRemoveDotSegments|purell.FlagRemoveDuplicateSlashes|purell.FlagRemoveUnnecessaryHostDots|purell.FlagRemoveEmptyPortSeparator)
  }
docs: // SanitizeURLKeepTrailingSlash is the same as SanitizeURL, but will keep any trailing slash.