Take my balance of a coin and use the whole balance in a market trade

In the app I can press the MAX button to use all of my balance of a coin to do a buy or convert.

How would I do that using Python ?

I've tried this ...

```
balance = client.get_crypto_balance("USDC")
client.fiat_market_buy("XRP-USDC", balance)
```

... but got a whole bunch of errors.

I guess it's because the amount is not a whole number?

Hope you can help.

Thanks,

Paully
