从dict python列表中删除重复项

Question

我有一个字典列表，我想从列表中删除重复项。怎么做？你知道吗

a = [
 {'dtstart': '2014-09-10T08:00:00',
  'end': datetime.datetime(2014, 9, 10, 9, 0),
  'location': 'Brady Auditorium, B-131',
  'partial_date': datetime.date(2014, 9, 10),
  'photo': 'http://tools.medicine.yale.edu/portal/stream?id=01a331e2-42be-4622-b072-0c42b55b436e&w=540&h=700',
  'start': datetime.datetime(2014, 9, 10, 8, 0),
  'stream': '01a331e2-42be-4622-b072-0c42b55b436e',
  'summary': 'Clinical Neuroscience Grand Rounds: "The Mechanism of Impaired Consciousness of Absence Seizures"',
  'uid': '2d671415-c666-498f-a401-01652a08e4b3'},
 {'dtstart': '2014-09-10T08:00:00',
  'end': datetime.datetime(2014, 9, 10, 9, 0),
  'location': 'Brady Auditorium, B-131',
  'partial_date': datetime.date(2014, 9, 10),
  'photo': 'http://tools.medicine.yale.edu/portal/stream?id=ccf667b2-b5a0-464f-8797-66eb36b0bf6c&w=540&h=700',
  'start': datetime.datetime(2014, 9, 10, 8, 0),
  'stream': 'ccf667b2-b5a0-464f-8797-66eb36b0bf6c',
  'summary': 'Clinical Neuroscience Grand Rounds: "The Mechanism of Impaired Consciousness of Absence Seizures"',
  'uid': '2d671415-c666-498f-a401-01652a08e4b3'}
]

我试过的是

>>> [dict(t) for t in set([tuple(d.items()) for d in a])]

但仍然返回重复的元素。你知道吗

Answer 1

尝试将UID附加到临时列表，并使用当前词典进行验证

import datetime

a=[{'end': datetime.datetime(2014, 9, 10, 9, 0), 'uid': '2d671415-c666-498f-a401-01652a08e4b3', 'stream': '01a331e2-42be-4622-b072-0c42b55b436e', 'photo': 'http://tools.medicine.yale.edu/portal/stream?id=01a331e2-42be-4622-b072-0c42b55b436e&w=540&h=700', 'partial_date': datetime.date(2014, 9, 10), 'summary': 'Clinical Neuroscience Grand Rounds: "The Mechanism of Impaired Consciousness of Absence Seizures"', 'start': datetime.datetime(2014, 9, 10, 8, 0), 'location': 'Brady Auditorium, B-131', 'dtstart': '2014-09-10T08:00:00'},
   {'end': datetime.datetime(2014, 9, 10, 9, 0), 'uid': '2d671415-c666-498f-a401-01652a08e4b3', 'stream': 'ccf667b2-b5a0-464f-8797-66eb36b0bf6c', 'photo': 'http://tools.medicine.yale.edu/portal/stream?id=ccf667b2-b5a0-464f-8797-66eb36b0bf6c&w=540&h=700', 'partial_date': datetime.date(2014, 9, 10), 'summary': 'Clinical Neuroscience Grand Rounds: "The Mechanism of Impaired Consciousness of Absence Seizures"', 'start': datetime.datetime(2014, 9, 10, 8, 0), 'location': 'Brady Auditorium, B-131', 'dtstart': '2014-09-10T08:00:00'}]

uuids = set() # temperary set holds UID
final=[]

for i in a:
    if i['uid'] not in uuids:
        final.append(i)
        uuids.add(i['uid'])
print final

Answer 2

使用字典理解创建一个以uid为键、以每个字典为值的字典。然后提取值以返回由uid键控的唯一字典列表。你知道吗

>>> a=[{'end': datetime.datetime(2014, 9, 10, 9, 0), 'uid': '2d671415-c666-498f-a401-01652a08e4b3', 'stream': '01a331e2-42be-4622-b072-0c42b55b436e', 'photo': 'http://tools.medicine.yale.edu/portal/stream?id=01a331e2-42be-4622-b072-0c42b55b436e&w=540&h=700', 'partial_date': datetime.date(2014, 9, 10), 'summary': 'Clinical Neuroscience Grand Rounds: "The Mechanism of Impaired Consciousness of Absence Seizures"', 'start': datetime.datetime(2014, 9, 10, 8, 0), 'location': 'Brady Auditorium, B-131', 'dtstart': '2014-09-10T08:00:00'}, {'end': datetime.datetime(2014, 9, 10, 9, 0), 'uid': '2d671415-c666-498f-a401-01652a08e4b3', 'stream': 'ccf667b2-b5a0-464f-8797-66eb36b0bf6c', 'photo': 'http://tools.medicine.yale.edu/portal/stream?id=ccf667b2-b5a0-464f-8797-66eb36b0bf6c&w=540&h=700', 'partial_date': datetime.date(2014, 9, 10), 'summary': 'Clinical Neuroscience Grand Rounds: "The Mechanism of Impaired Consciousness of Absence Seizures"', 'start': datetime.datetime(2014, 9, 10, 8, 0), 'location': 'Brady Auditorium, B-131', 'dtstart': '2014-09-10T08:00:00'}]
>>> {d['uid']: d for d in a}.values()
[{'dtstart': '2014-09-10T08:00:00',
  'end': datetime.datetime(2014, 9, 10, 9, 0),
  'location': 'Brady Auditorium, B-131',
  'partial_date': datetime.date(2014, 9, 10),
  'photo': 'http://tools.medicine.yale.edu/portal/stream?id=ccf667b2-b5a0-464f-8797-66eb36b0bf6c&w=540&h=700',
  'start': datetime.datetime(2014, 9, 10, 8, 0),
  'stream': 'ccf667b2-b5a0-464f-8797-66eb36b0bf6c',
  'summary': 'Clinical Neuroscience Grand Rounds: "The Mechanism of Impaired Consciousness of Absence Seizures"',
  'uid': '2d671415-c666-498f-a401-01652a08e4b3'}]

Answer 3

只需尝试以下代码：

{document['uid']: document for document in a}.values()

对于每一个uuid您都会得到最新的文档。如果要查找第一个条目，请尝试以下操作：

{document['uid']: document for document in a[::-1]}.values()