code: func (api *API) PurgeEverything(zoneID string) (PurgeCacheResponse, error) {
  	uri := "/zones/" + zoneID + "/purge_cache"
  	res, err := api.makeRequest("DELETE", uri, PurgeCacheRequest{true, nil, nil, nil})
  	if err != nil {
  		return PurgeCacheResponse{}, errors.Wrap(err, errMakeRequestError)
  	}
  	var r PurgeCacheResponse
  	err = json.Unmarshal(res, &r)
  	if err != nil {
  		return PurgeCacheResponse{}, errors.Wrap(err, errUnmarshalError)
  	}
  	return r, nil
  }
docs: // PurgeEverything purges the cache for the given zone.
  //
  // Note: this will substantially increase load on the origin server for that
  // zone if there is a high cached vs. uncached request ratio.
  //
  // API reference: https://api.cloudflare.com/#zone-purge-all-files