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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pwallet->m_pay_tx_fee = tx_fee_rate;
    return true;
}
static UniValue getbalances(const JSONRPCRequest& request)
{
    std::shared_ptr<CWallet> const rpc_wallet = GetWalletForJSONRPCRequest(request);
    if (!EnsureWalletIsAvailable(rpc_wallet.get(), request.fHelp)) {
        return NullUniValue;
    }
    CWallet& wallet = *rpc_wallet;
    RPCHelpMan{
        "getbalances",
        "Returns an object with all balances in " + CURRENCY_UNIT + ".\n",
        {},
        RPCResult{
            RPCResult::Type::OBJ, "", "",
            {
                {RPCResult::Type::OBJ, "mine", "balances from outputs that the wallet can sign",
                {
                    {RPCResult::Type::STR_AMOUNT, "trusted", "trusted balance (outputs created by the wallet or confirmed outputs)"},
                    {RPCResult::Type::STR_AMOUNT, "untrusted_pending", "untrusted pending balance (outputs created by others that are in the mempool)"},
                    {RPCResult::Type::STR_AMOUNT, "immature", "balance from immature coinbase outputs"},
                    {RPCResult::Type::STR_AMOUNT, "used", "(only present if avoid_reuse is set) balance from coins sent to addresses that were previously spent from (potentially privacy violating)"},
                }},
                {RPCResult::Type::OBJ, "watchonly", "watchonly balances (not present if wallet does not watch anything)",
                {
                    {RPCResult::Type::STR_AMOUNT, "trusted", "trusted balance (outputs created by the wallet or confirmed outputs)"},
                    {RPCResult::Type::STR_AMOUNT, "untrusted_pending", "untrusted pending balance (outputs created by others that are in the mempool)"},
                    {RPCResult::Type::STR_AMOUNT, "immature", "balance from immature coinbase outputs"},
                }},