code: function(callback, method, path, queryParams, data,
                                        prefix, localTimeoutMs) {
          return this.authedRequest(
              callback, method, path, queryParams, data, {
                  localTimeoutMs: localTimeoutMs,
                  prefix: prefix,
              },
          );
      }
docs: Perform an authorised request to the homeserver with a specific path
  prefix which overrides the default for this call only. Useful for hitting
  different Matrix Client-Server versions.
  @param {Function} callback Optional. The callback to invoke on
  success/failure. See the promise return values for more information.
  @param {string} method The HTTP method e.g. "GET".
  @param {string} path The HTTP path <b>after</b> the supplied prefix e.g.
  "/createRoom".
  @param {Object} queryParams A dict of query params (these will NOT be
  urlencoded).
  @param {Object} data The HTTP JSON body.
  @param {string} prefix The full prefix to use e.g.
  "/_matrix/client/v2_alpha".
  @param {Number=} localTimeoutMs The maximum amount of time to wait before
  timing out the request. If not specified, there is no timeout.
  @return {module:client.Promise} Resolves to <code>{data: {Object},
  headers: {Object}, code: {Number}}</code>.
  If <code>onlyData</code> is set, this will resolve to the <code>data</code>
  object only.
  @return {module:http-api.MatrixError} Rejects with an error if a problem
  occurred. This includes network problems and Matrix-specific error JSON.
  
  @deprecated prefer authedRequest with opts.prefix