// ReadCheckSums reads the values back.
func (c *Checksum) AppendTo(b []byte, parts []byte) []byte {
	if c == nil {
		return nil
	}
	var tmp [binary.MaxVarintLen32]byte
	n := binary.PutUvarint(tmp[:], uint64(c.Type))
	crc := c.Raw
	if len(crc) != c.Type.RawByteLen() {
		return b
	}
	b = append(b, tmp[:n]...)
	b = append(b, crc...)
	if c.Type.Is(ChecksumMultipart) {
		var checksums int

pkg encoding/binary, const MaxVarintLen16 ideal-int
pkg encoding/binary, const MaxVarintLen32 ideal-int
pkg encoding/binary, const MaxVarintLen64 ideal-int
pkg encoding/binary, func PutUvarint([]uint8, uint64) int
pkg encoding/binary, func PutVarint([]uint8, int64) int
pkg encoding/binary, func Read(io.Reader, ByteOrder, interface{}) error
pkg encoding/binary, func ReadUvarint(io.ByteReader) (uint64, error)