python - 为什么这段代码没有实时下载数据？

Question

我有一个我不知道如何解决的问题（我是编码初学者）。该程序应该从 yahoo Finance 中抓取股票价格数据：

import bs4
from bs4 import BeautifulSoup
import requests
import pandas as pd
import datetime as dt

def real_time_price(stock_code):
   url = 'https://finance.yahoo.com/quote/' + stock_code + '/'
   r = requests.get(url)

   web_content = BeautifulSoup(r.text, 'lxml')
   web_content = web_content.find('div', {'class':'My(6px) Pos(r) smartphone_Mt(6px)'})
   web_content = web_content.find('span').text

   if web_content==[]:
       web_content = '999999'

   return web_content

LA = ['AAPL', 'FB', 'F', 'AMZN', 'GOOG']

for step in range(1,101):
    price = []
    col = []#Lista, która dodaje dane do df
    time_stamp = dt.datetime.now()
    time_stamp = time_stamp.strftime('%Y-%m-%d %H:%M:%S')
    for stock_code in LA:
        price.append(real_time_price(stock_code))
    col = [time_stamp]
    col.extend(price)
    df = pd.DataFrame(col)
    df = df.T
    df.to_csv('realtimestockdata.csv', mode = 'a', header = False)
    print(col)

但它似乎在运行时没有更新，我错过了一些语法错误吗？

所有回复都非常感谢，谢谢。