Authorization of Moya Swift

I try to get a list of languages ​​from https://gateway.watsonplatform.net/language-translator/api/v3/identifiable_languages/?version=2018-05-01 I use moya

let newsApiProvider = MoyaProvider<NewsApi>(plugins: [CredentialsPlugin { target -> URLCredential? in return URLCredential(user: "user", password: "password", persistence: .none) } ]) extension NewsApi: TargetType { public var task: Task { return .requestParameters(parameters: ["version": "2018-05-01"], encoding: URLEncoding.default) } public var baseURL: URL { return URL(string: "https://gateway.watsonplatform.net/language-translator/api")! } public var path: String { return "/v3/identifiable_languages" } public var method: Moya.Method { return .get } public var sampleData: Data { return Data() } public var headers: [String : String]? { return nil } 

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