Function: update_stock_price
This tool belongs to the trading system, which allows users to trade stocks, manage their account, and view stock information. Tool description: Update the price of a stock.
Parameters: symbol: type: string
description: Symbol of the stock to update.
new_price: type: float
description: New price of the stock. 
Required parameters: symbol, new_price
Response: symbol: type: string
description: Symbol of the updated stock.
old_price: type: float
description: Previous price of the stock.
new_price: type: float
description: Updated price of the stock.