fn release(env: soroban_sdk::Env) -> i128
fn upgrade(
env: soroban_sdk::Env,
hash: soroban_sdk::BytesN<32>,
) -> Result<(), soroban_sdk::Error>
fn initialize(
env: soroban_sdk::Env,
admin: soroban_sdk::Address,
token: soroban_sdk::Address,
fund: soroban_sdk::Address,
rewards: soroban_sdk::Address,
ledger: u32,
) -> Result<(), soroban_sdk::Error>