Python 从字典列表的列表中创建列表

Question

我有一个列表，它在名为enclosures 的列表中包含有关 ZIP(它们的位置、大小等)的信息。

列表是用这段代码创建的:

for item in g.entries:
    enclosure = [l for l in item["links"] if l["rel"] == "enclosure"]
    if(len(enclosure)>0):
        enclosures.append(enclosure)

enclosures 列表中的每一项都具有以下格式:

>>> enclosures[0]
[{'type': 'application/zip', 'rel': 'enclosure', 'length': '57648', 'href': 'http://www.sec.gov/Archives/edgar/data/37748/000003774810000025/0000037748-10-000025-xbrl.zip'}]

或者另一个例子...

>>> enclosures[45]
[{'type': 'application/zip', 'rel': 'enclosure', 'length': '107907', 'href': 'http://www.sec.gov/Archives/edgar/data/1385157/000104746910004400/0001047469-10-004400-xbrl.zip'}]

我需要的是创建一个名为href 的列表，其中包含附件列表 中的每个href 项以相同的顺序。

以下这些尝试都失败了。

>>> enclosures[46]["href"]
Traceback (most recent call last):
  File "<pyshell#66>", line 1, in <module>
    enclosures[46]["href"]
TypeError: list indices must be integers, not str

>>> enclosures[46][4]
Traceback (most recent call last):
  File "<pyshell#67>", line 1, in <module>
    enclosures[46][4]
IndexError: list index out of range

编辑

亲爱的timgeb

我有这样的结果:

>>> href = [x['href'] for x in enclosures]
Traceback (most recent call last):
  File "<pyshell#75>", line 1, in <module>
    href = [x['href'] for x in enclosures]
  File "<pyshell#75>", line 1, in <listcomp>
    href = [x['href'] for x in enclosures]
TypeError: list indices must be integers, not str

Answer 1

href = [x[0]['href'] for x in enclosures]