The RPC docs are now enforced to specify the json type of the args and results at compile time. However, some help texts contain the type twice. (E.g. https://github.com/bitcoin/bitcoin/pull/17809#discussion_r386295217 ). The duplicate type in the description should be removed.

Duplicates can be found with this command:

```sh
git grep --extended-regexp  'RPC.*(ARR|OBJ).*json (array|object)' src/rpc/ src/wallet/rpc*
```

#### Useful skills:

Basic understanding of how to compile and run Bitcoin Core.

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{
    RPCHelpMan{
        "createwallet",
        "\nCreates and loads a new wallet.\n",
        {
            {"wallet_name", RPCArg::Type::STR, RPCArg::Optional::NO, "The name for the new wallet. If this is a path, the wallet will be created at the path location."},
            {"disable_private_keys", RPCArg::Type::BOOL,  "false", "Disable the possibility of private keys (only watchonlys are possible in this mode)."},
            {"blank", RPCArg::Type::BOOL,  "false", "Create a blank wallet. A blank wallet has no keys or HD seed. One can be set using sethdseed."},
            {"passphrase", RPCArg::Type::STR, RPCArg::Optional::OMITTED, "Encrypt the wallet with this passphrase."},
            {"avoid_reuse", RPCArg::Type::BOOL,  "false", "Keep track of coin reuse, and treat dirty and clean coins differently with privacy considerations in mind."},
        },
        RPCResult{
            RPCResult::Type::OBJ, "", "",
            {
                {RPCResult::Type::STR, "name", "The wallet name if created successfully. If the wallet was created using a full path, the wallet_name will be the full path."},
                {RPCResult::Type::STR, "warning", "Warning message if wallet was not loaded cleanly."},
            }
        },
        RPCExamples{
            HelpExampleCli("createwallet", "\"testwallet\"")
            + HelpExampleRpc("createwallet", "\"testwallet\"")
        },
    }.Check(request);
    uint64_t flags = 0;
    if (!request.params[1].isNull() && request.params[1].get_bool()) {
        flags |= WALLET_FLAG_DISABLE_PRIVATE_KEYS;
    }