Q:

Python bot game

Below code works fine when I use !luck xx and when the amount is low it will say the amount is low, but when I use !luck -xx it still keeps adding the amount.
So how to disable using the -xx amount
@bot.command(pass_context=True)
async def luck(ctx, amounty: int):
    primary_id = ctx.message.author.id
    if primary_id not in amounts:
        await bot.say("not registered")
    elif amounts[primary_id] < amounty:
        await bot.say("low balance")
    else:
        amounts[primary_id] -= amounty
        a = random.randint(1,2)
        if a == 1:
            amounts[primary_id] += amounty * 2
            await bot.say("You Won")
        else:
            await bot.say("You lost")

A:

Just check if the number is negative and if so do an empty return
  if amounty<0:
    await bot.say("Can't use a negative number")
    return

