toCbor method
Converts the object to a CBOR object.
Implementation
@override
CborObject toCbor() {
  switch (serializationConfig.encoding) {
    case CborMapEncodingType.definite:
      return CborMapValue.definite({
        for (final i in assets.entries)
          i.key.toCbor(): CborUnsignedValue.u64(i.value)
      });
    case CborMapEncodingType.inDefinite:
      return CborMapValue.inDefinite({
        for (final i in assets.entries)
          i.key.toCbor(): CborUnsignedValue.u64(i.value)
      });
  }
}