python爬取数据无法写入csv

Question

我用Python爬虫爬取了豆瓣上的数据，但是在写入csv的时候确死活写不进去（csv文件空白）···
以下是回调写入数据类：

class ScrapeCallback:
    def __init__(self):
        self.writer = csv.writer(open('countries.csv', 'w', newline=''))
        self.fields = ('name', 'year', 'score')
        self.writer.writerow(self.fields)

    def __call__(self, url, html):
        csslist = ['span[property = "v:itemreviewed"]', 'span.year', 'strong[property="v:average"]']
        try:
            tree = lxml.html.fromstring(html)
            row = [tree.cssselect('{0}'.format(field))[0].text for field in csslist]
            #写入csv
            self.writer.writerow(row)
            print(url, row)
        except Exception as e:
                print("ScrapeCallback error:", e)

print语句是正常显示的，说明函数没报错。请大神找一下错误原因，十分感谢
附源码

Answer 1

问题已解决
原因：强制结束进程导致文件未正常关闭