let credentialsProvider = AWSCognitoCredentialsProvider(regionType: config.region, identityPoolId: config.identityPoolId)
let configuration = AWSServiceConfiguration(region: config.region, credentialsProvider: credentialsProvider)
AWSServiceManager.default().defaultServiceConfiguration = configuration

func setupGatewayClient() {
    guard let configuration = AWSServiceManager.default().defaultServiceConfiguration else {
      return
    }
    gatewayClient = AWSAPIGatewayClient()
    gatewayClient.configuration = configuration.copy() as! AWSServiceConfiguration
    let URLString: String = <My endpont URL>
    let endpoint = AWSEndpoint(region: configuration.regionType, service: .APIGateway, url: URL(string: URLString))
    gatewayClient.configuration.endpoint = endpoint

    let signer: AWSSignatureV4Signer = AWSSignatureV4Signer(credentialsProvider: configuration.credentialsProvider, endpoint: endpoint)
    if let endpoint = endpoint {
        gatewayClient.configuration.baseURL = endpoint.url
    }
    gatewayClient.configuration.requestInterceptors = [AWSNetworkingRequestInterceptor(), signer]
  }