Difficulty – Proof of Work: Compare Computed Hash with Target Hash

According to the source code, here’s where the hash calculated by the miner is compared to the target hash:

bool CheckProofOfWork(uint256 hash, unsigned int nBits, const Consensus::Params& params)
{
    bool fNegative;
    bool fOverflow;
    arith_uint256 bnTarget;

    bnTarget.SetCompact(nBits, &fNegative, &fOverflow);

    // Check range
    if (fNegative || bnTarget == 0 || fOverflow || bnTarget > UintToArith256(params.powLimit))
        return false;

    // Check proof of work matches claimed amount
    if (UintToArith256(hash) > bnTarget)
        return false;

    return true;
}

Can you please comment the code above to help me understand the role of all the variables used in this function?

I read this about comparing hashes, but anyway, can I make another example that prints the hash string to show the output of every line of code?