compress.go
func WriteGzip(w io.Writer, p []byte) (int, error) {
	return WriteGzipLevel(w, p, CompressDefaultCompression)
}
func WriteGzip(w io.Writer, p []byte) (int, error) {
	return WriteGzipLevel(w, p, CompressDefaultCompression)
}
// WriteGzip writes gzipped p to w and returns the number of compressed
// bytes written to w.