匿名函数lambda map(lambda url:BASE_DOMAIN + url,detail_urls) map这行代码意为构建一个新的字典detail_urls,键为数字序号,值与之前一致 等价代码如下: def aaa(url): return BASE_DOMAIN + url iii = 0 for detail_url in detail_urls: detail_urls[index] = aaa(detail_url) index += 1