open fun copy(url: String = this.url, method: String = this.method, headers: Map<String, String> = this.headers, body: dynamic = this.body, referrer: String? = this.referrer, referrerPolicy: dynamic = this.referrerPolicy, mode: RequestMode? = this.mode, credentials: RequestCredentials? = this.credentials, cache: RequestCache? = this.cache, redirect: RequestRedirect? = this.redirect, integrity: String? = this.integrity, keepalive: Boolean? = this.keepalive, reqWindow: Any? = this.reqWindow, middlewares: List<Middleware> = this.middlewares): Request
creates a copy of the Request.