TypeScript Error: 'RelayProvider' is not assignable to parameter of type 'ExternalProvider | JsonRpcFetchFunc' about gsn-with-ethers HOT 3 OPEN

class WrappedRelayProvider extends RelayProvider implements ethers.providers.ExternalProvider {

    send(request: { method: string, params?: Array<any> }, callback: (error: any, response: any) => void | undefined): void {
        super.send({
            jsonrpc: '2.0',
            method: request.method,
            params: request.params ?? []
        }, callback)
    }

}

const relayConfing = {
    paymasterAddress: CONFIG.PAYMASTER_ADDRESS
}
 const gsnProvider = (await gsn.RelayProvider.newProvider({ provider: ethereum, config: relayConfing }).init()) as WrappedRelayProvider
const ethersProvider = new ethers.providers.Web3Provider(gsnProvider )