SWIFT - APIClient / SWAPI my final class doesnt conform to my APIClient, but i cant figure out why?! please help :)

protocol APIClient {
    var configuration: URLSessionConfiguration { get }
    var session: URLSession { get }

    init(config: URLSessionConfiguration)

    func jsonTask(withRequest request: URLRequest, completion: @escaping JSONTaskCompletion) -> JSONTask
    func fetch<T: JSONDecodable>(request: URLRequest, parse: (JSON) -> T?, completion: (APIResult<T>) -> Void)
}



extension APIClient {
    func jsonTask(withRequest request: URLRequest, completion: @escaping JSONTaskCompletion) -> JSONTask {

        let task = session.dataTask(with: request, completionHandler: { data, response, error in

            guard let HTTPResponse = response as? HTTPURLResponse else {
                let userInfo = [
                    NSLocalizedDescriptionKey: NSLocalizedString("Missing HTTP Response", comment: "")
                ]

                let error = NSError(domain: TRENetworkingErrorDomain, code: MissingHTTPResponseError, userInfo: userInfo)
                completion(nil, nil, error)
                return
            }

            if data == nil {
                if let error = error {
                    completion(nil, HTTPResponse, error as NSError?)
                }
            } else {
                switch HTTPResponse.statusCode {
                case 200:
                    do {
                        let json = try JSONSerialization.jsonObject(with: data!, options: []) as? [String : AnyObject]
                        completion(json, HTTPResponse, nil)
                    } catch let error as NSError {
                        completion(nil, HTTPResponse, error)
                    }
                default: print("Received HTTP Response: \(HTTPResponse.statusCode) - not handled")
                }
            }
        })

        return task
    }

    func fetch<T>(_ request: URLRequest, parse: @escaping (JSON) -> T?, completion: @escaping (APIResult<T>) -> Void) {

        let task = jsonTask(withRequest: request) { json, response, error in

            DispatchQueue.main.async {
                guard let json = json else {
                    if let error = error {
                        completion(.failure(error))
                    } else {
                        // TODO: Implement Error Handling
                    }
                    return
                }

                if let value = parse(json) {
                    completion(.success(value))
                } else {
                    let error = NSError(domain: TRENetworkingErrorDomain, code: UnexpectedResponseError, userInfo: nil)
                    completion(.failure(error))
                }
            }
        }

        task.resume()
    }
}

final class StarWarsAPIClient: APIClient {

    var configuration: URLSessionConfiguration
    lazy var session: URLSession = {
        return URLSession(configuration: self.configuration)
    }()


    init(config: URLSessionConfiguration) {
        self.configuration = config
    }

    convenience init() {
        self.init(config: URLSessionConfiguration.default)
    }

    func fetchStarWars(type: StarWarsType, completion: @escaping (APIResult<People>) -> Void) {
        let request = StarWarsType.people.request


        fetch(request, parse: { json -> People? in
            // parse from JSON response to Types

            if let typesDictionary = json as? [String : AnyObject] {
                return People(JSON: typesDictionary)
            } else {
                return nil
            }


        }, completion: completion)
    }
    }