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特定格式的Python字典输出列表

boto3 python-3.x python

Ajay Misra · 技术社区 · 3 年前

您好,我是python新手,这可能很小,但我发现如何获得特定格式的输出很困难。

我有下面的目录被退回

vpcs = [{'ResourceOwnerId': '111111111111', 'ResourceType': 'vpc', 'ResourceId': 'vpc-aaaaa'},
        {'ResourceOwnerId': '222222222222', 'ResourceType': 'vpc', 'ResourceId': 'vpc-ccccc'}
        {'ResourceOwnerId': '111111111111', 'ResourceType': 'vpc', 'ResourceId': 'vpc-ddddd'}]

下面是我的脚本片段

for vpc in vpcs:
        acc_data = {
            "account_number": vpc["ResourceOwnerId"],
            "vpc": [vpc['ResourceId']]
        }
        acc_list.append(acc_data)

print(acc_list)

其输出如下

        [
            {'account_number': '111111111111', 'vpc': ['vpc-aaaaa']},
            {'account_number': '222222222222', 'vpc': ['vpc-ccccc']},
            {'account_number': '111111111111', 'vpc': ['vpc-ddddd']}
        ]

而我想要这样的输出

        [
            {'account_number': '111111111111', 'vpc': ['vpc-aaaaa', 'vpc-ddddd']},
            {'account_number': '222222222222', 'vpc': ['vpc-ccccc']}
        ]

i、 e.“账号”与这些专有网络相同,因此应追加该账号,而不是创建新条目。任何帮助都将不胜感激谢谢

4 回复 | 直到 3 年前

Mark 3 年前

你可以用 dict.setdefault 当第一次看到密钥时,创建一个空列表的基本子目录。然后再加上。最终结果将是 dict.values() :

vpcs = [{'ResourceOwnerId': '111111111111', 'ResourceType': 'vpc', 'ResourceId': 'vpc-aaaaa'},
        {'ResourceOwnerId': '222222222222', 'ResourceType': 'vpc', 'ResourceId': 'vpc-ccccc'},
        {'ResourceOwnerId': '111111111111', 'ResourceType': 'vpc', 'ResourceId': 'vpc-ddddd'}]

groups = {}

for d in vpcs:
    k = d['ResourceOwnerId']
    groups.setdefault(k, {'account_number':k, 'vpc':[]} )['vpc'].append(d['ResourceId'])
    
list(groups.values())

这将给你:

[{'account_number': '111111111111', 'vpc': ['vpc-aaaaa', 'vpc-ddddd']},
 {'account_number': '222222222222', 'vpc': ['vpc-ccccc']}]

Tim Roberts 3 年前

分两个阶段进行。使用字典建立唯一列表,然后转换为字典列表:

from collections import defaultdict

vpcs = [{'ResourceOwnerId': '111111111111', 'ResourceType': 'vpc', 'ResourceId': 'vpc-aaaaa'},
        {'ResourceOwnerId': '222222222222', 'ResourceType': 'vpc', 'ResourceId': 'vpc-ccccc'},
        {'ResourceOwnerId': '111111111111', 'ResourceType': 'vpc', 'ResourceId': 'vpc-ddddd'}]

accum = defaultdict(list)
for vpc in vpcs:
    accum[vpc['ResourceOwnerId']].append( vpc['ResourceId'] )

print(accum)

acc_list = []
for k, v in accum.items():
    acc_list.append(
        {
            "account_number": k,
            "vpc": v
        }
    )

print(acc_list)

输出:

defaultdict(<class 'list'>, {'111111111111': ['vpc-aaaaa', 'vpc-ddddd'], '222222222222': ['vpc-ccccc']})
[{'account_number': '111111111111', 'vpc': ['vpc-aaaaa', 'vpc-ddddd']}, {'account_number': '222222222222', 'vpc': ['vpc-ccccc']}]

或者,对于那些喜欢一句台词的人:

...
acc_list = [ { "account_number": k, "vpc": v } for k, v in accum.items()]
print(acc_list)

Codeman 3 年前

    from copy import deepcopy # create a copy of a list.
    # Your code snippet
    for vpc in vpcs:
        acc_data = {
            "account_number": vpc["ResourceOwnerId"],
            "vpc": [vpc['ResourceId']]
        }
        acc_list.append(acc_data)

    # Add this
    new_acc_list = deepcopy(acc_list)
    previous_acc_numbers = {} # int: index

    for acc_data in acc_list:
        acc_number, acc_vpc = acc_data.get(account_number), acc_data.get("vpc")
        if acc_number in previous_acc_numbers:
            new_acc_list[previous_acc_numbers.get(acc_number)].get("vpc").append(acc_data.get("vpc"))
    
    print(acc_list)

not_speshal 3 年前

尝试创建一个字典,将账号映射到VPC。然后转换这本字典:

dct = dict()
for vpc in vpcs:
    if vpc["ResourceOwnerId"] not in dct:
        dct[vpc["ResourceOwnerId"]] = list()
    dct[vpc["ResourceOwnerId"]].append(vpc["ResourceId"])

output = [{"account_number": k, "vpc": v} for k,v in dct.items()]

>>> output
[{'account_number': '111111111111', 'vpc': ['vpc-aaaaa', 'vpc-ddddd']},
 {'account_number': '222222222222', 'vpc': ['vpc-ccccc']}]