func cipherblock(dek []byte) (cipherblock cipher.Block) {
	cipherblock, err := aes.NewCipher(dek)
	check(err)
	return
}
//cipherblock creates and returns a new aes cipher.Block
cipherblock creates and returns a new aes cipher.Block
// cipherblock creates and returns a new aes cipher . Block
func cipherblock(dek []byte) (cipherblock cipher.Block) {
	cipherblock, err := aes.NewCipher(dek)
	check(err)
	return
}
func cipherblock ( dek [ ] byte ) ( cipherblock cipher . Block ) { cipherblock , err := aes . NewCipher ( dek ) check ( err ) return }
cipherblock creates and returns a new aes cipher.Block
cipherblock creates and returns a new aes cipher . Block