Function simfony_as_rust::jet::transaction::input_script_sig_hash

pub fn input_script_sig_hash(a: u32) -> Option<u256>

Return the SHA256 hash of the scriptSigKey of the input at the given index.

Return None if the input does not exist.

SegWit UTXOs enforce scriptSig to be the empty string. In such cases, we return the SHA256 hash of the empty string.