pub fn is_local_cumulative_sum_failing(&self) -> bool {
        matches!(
            self,
            MachineVerificationError::InvalidShardProof(VerificationError::CumulativeSumsError(
                "local cumulative sum is not zero"
            ))
        )
    }
This function will check if the verification error is from local cumulative sum failing.
crates/stark/src/machine.rs