 import WebKit
 
 class InstagramLoginViewController: UIViewController {
-
-    // MARK: - Constants
-
-    private final let observerKeyPath = "estimatedProgress"
 
     // MARK: - Properties
 

        }
    }

    public func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction,
                        decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {
        let urlString = navigationAction.request.url!.absoluteString

        if let range = urlString.range(of: "#access_token=") {

        fatalError("init(coder:) has not been implemented")
    }

    public init(clientId: String, authScope: String, redirectURI: String, completion: @escaping (String?, InstagramError?) -> Void) {
        self.clientId = clientId
        self.authScope = authScope
        self.redirectURI = redirectURI
