`UpgradePurposeType`

enum UpgradePurposeType : uint8 {
    ConsensusParameters = 0,
    StateTransition = 1,
}

name	type	description
`type`	`UpgradePurposeType`	Type of upgrade purpose.
`data`	One of `ConsensusParameters`, `StateTransition`	Upgrade purposes.

Transaction is invalid if:

`ConsensusParameters`

name	type	description
`witnessIndex`	`uint16`	Index of witness that contains a serialized(with postcard) consensus parameters.
`checksum`	`byte[32]`	The hash of the serialized consensus parameters.

Given helper deserialize_consensus_parameters() that deserializes the consensus parameters from a witness by using postcard algorithm.

Transaction is invalid if:

witnessIndex >= tx.witnessesCount
checksum != sha256(tx.data.witnesses[witnessIndex])
deserialize_consensus_parameters(tx.data.witnesses[witnessIndex]) returns an error.

name	type	description
`bytecodeRoot`	`byte[32]`	The root of the new bytecode of the state transition function.