Serialize data of type T to type S, eg. a String or some binary representation.
unmarshal(marshal(data)) must produce an instance of T that is equivalent to
original instance data.
unmarshal(dynamicdata, [MarshalingContext?context])
→ T
Deserialize a representation of type S back to the original data of type T.
unmarshal(marshal(data)) must produce an instance of T that is equivalent to
original instance data.