fn upgrade(
env: soroban_sdk::Env,
contract_address: soroban_sdk::Address,
new_version: soroban_sdk::String,
new_wasm_hash: soroban_sdk::BytesN<32>,
migration_data: soroban_sdk::Vec,
) -> Result<(), ContractError>
fn __constructor(env: soroban_sdk::Env)