func newGzipResponseWriter(w http.ResponseWriter) *gzipResponseWriter {
var gz *gzip.Writer
if gzI := gzipWriterPool.Get(); gzI == nil {
gz = gzip.NewWriter(w)
} else {
gz = gzI.(*gzip.Writer)
gz.Reset(w)
}
return &gzipResponseWriter{WriteCloser: gz, ResponseWriter: w}
}