the command "bitcoin-cli getblockstats 0000000000000000000c61ff8f761ce509fc8901d3c22d61fec89637042ea2ba" does not work.

It displays "error: Error parsing JSON:0000000000000000000c61ff8f761ce509fc8901d3c22d61fec89637042ea2ba"

but it should display the block stats like the documentation says.

also bitcoin-cli getblockstats 0 does not work. block number must be at least 1 to work. But blocks start at 0.

tested with 0.20.1 on freebsd, another user on IRC acknowledged the problem.
+ HelpExampleRpc("preciousblock", "\"blockhash\"")
                },
        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
{
    uint256 hash(ParseHashV(request.params[0], "blockhash"));
    CBlockIndex* pblockindex;
    ChainstateManager& chainman = EnsureAnyChainman(request.context);
    {
        LOCK(cs_main);
        pblockindex = chainman.m_blockman.LookupBlockIndex(hash);
        if (!pblockindex) {
            throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
        }
    }
    BlockValidationState state;
    chainman.ActiveChainstate().PreciousBlock(state, pblockindex);
    if (!state.IsValid()) {
        throw JSONRPCError(RPC_DATABASE_ERROR, state.ToString());
    }
    return UniValue::VNULL;
},
    };
}
static RPCHelpMan invalidateblock()
{
    return RPCHelpMan{"invalidateblock",
                "\nPermanently marks a block as invalid, as if it violated a consensus rule.\n",
                {
                    {"blockhash", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "the hash of the block to mark as invalid"},
                },