How can I change Locale.current?

[diamid6]

Could you please advise me, how can I change Locale.current here:
private static func tr(_ table: String, _ key: String, _ args: CVarArg..., fallback value: String) -> String { let format = BundleToken.bundle.localizedString(forKey: key, value: value, table: table) return String(format: format, locale: Locale.current, arguments: args) }