Function base58check_encode 

pub fn base58check_encode(payload: &[u8]) -> String

Bitcoin-alphabet Base58Check: Base58(payload ‖ checksum4).

checksum4 is the first 4 bytes of double_sha256 over payload. Callers supply the full pre-checksum body (e.g. version ‖ hash160 for P2PKH, or WIF’s version ‖ sk ‖ 0x01).