使用re.match时输入错误

Question

我调用了re.match，但错误表明该列表需要一个整数而不是字符串。

tripadvisor_item['avg_stars'] = re.match(r'(\S+)', snode_restaurant_item_avg
_stars).group()
TypeError: list indices must be integers, not str

这是代码，

# Build item index.
for snode_restaurant in snode_restaurants:
    # Cleaning string and taking only the first part before whitespace.
    snode_restaurant_item_avg_stars = clean_parsed_string(get_parsed_string(snode_restaurant, 'div[@class="wrap"]/div[@class="entry wrap"]/div[@class="description"]/div[@class="wrap"]/div[@class="rs rating"]/span[starts-with(@class, "rate")]/img[@class="sprite-ratings"]/@alt'))
    tripadvisor_item['avg_stars'] = re.match(r'(\S+)', snode_restaurant_item_avg_stars).group()*

    # Popolate reviews and address for current item.
    yield Request(url=tripadvisor_item['url'], meta={'tripadvisor_item': tripadvisor_item}, callback=self.parse_fetch_review)

即使在文档中也是如此，

"""Try to apply the pattern at the start of the string, returning
    a match object, or None if no match was found."""