多列表理解

items = [
   [{'URL': '1234'}, {'ID': 1}],
   [{'URL': '12344321'}, {'ID': 2}]
]
print [i[0]['URL'] for i in items]

抓住钥匙的价值 URL

如果您可以在单个列表中使用多个词典

print [j['URL'] for i in items for j in i]