input: Write a python function to get stock data for a given stock name and plot a graph of its daily prices.
  assert "date" in stock_data("AAPL").keys()
  assert "price" in stock_data("AAPL").keys()
  assert "graph" in stock_data("AAPL").keys()
output: import yfinance as yf
  import matplotlib.pyplot as plt
  
  def stock_data(stock_name):
      stock = yf.Ticker(stock_name)
      hist = stock.history(period="1d", interval="1m")
  
      dates = hist.index.strftime('%Y-%m-%d %H:%M:%S').tolist()
      prices = hist['Close'].tolist()
  
      fig, ax = plt.subplots()
      ax.plot(dates, prices, label='Price')
      plt.xlabel('Date')
      plt.ylabel('Price')
      plt.title(f'Daily Prices for {stock_name}')
      plt.legend()
      plt.xticks(rotation=45)
      plt.tight_layout()
      plt.show()
  
      return {"date": dates, "price": prices, "graph": fig}