Swift 同步问题，发送Api Call之前未设置idToken

我是个新手，希望有人能帮我. bearerToken函数更新用于getMedicalData()函数的idToken变量 问题是getMedicalData()函数在idToken的值被bearerToken()更新之前运行.这会导致getMedicalData()使用一个空的idToken变量. 如何同步它，以便getMedicalData()在运行完所有bearerToken()之后运行.

getMedicalData()和bearerToken()的主要功能:

    func login(username: String, password: String) {
        _ = Amplify.Auth.signIn(
            username: username,
            password: password
        ) { [weak self] result in
            switch result {
            case .success(let signInResult):
                print(SignInResult.self)
                if signInResult.isSignedIn {
//calling the two functions
                    TokenManager.shared.bearerToken()
                    getMedicalData()

                    DispatchQueue.main.async {
                        self?.getCurrentAuthUser()
                    }
                }
                
            case .failure(let error):
                print("Login error:", error)
            }
        }
    }

bearerToken函数:

    func bearerToken() {
        _ = Amplify.Auth.fetchAuthSession { result in
            switch result {
            case .success(let session):
                if(session.isSignedIn) {
                    if let sess = session as? AWSAuthCognitoSession {
                        let result = sess.getCognitoTokens()
                        switch result {
                        case .success(let tokens):
                            self.idToken = String(tokens.idToken)
                            self.refreshToken = tokens.refreshToken
                        case .failure(let error):
                            print("Fetch user tokens failed with error \(error)")
                        }
                    }
                }
            case .failure(let error):
                print("Fetch session failed with error \(error)")
            }
        }
    }