python - 在for循环Python中的if语句中将一个键的值分配给另一个键

Question

我有一个 Python 字典列表。我遍历每个字典并检查给定的键是否存在。如果它确实存在，我检查这个键的值是否为空，如果它是空的，那么我需要在那个空键中保存另一个键的值。无法弄清楚如何将值从一个键分配给另一个键...

我的数据是这样的:

my_dicts = [{"Id": "123", "Campaign_Date": "2020-06-30", "Another_Date": "2020-07-01"}, {"Id": "125 ", "Campaign_Date": "", "Another_Date": "2020-07-01"}]

输出应该是这样的:

my_dicts = [{"Id": "123", "Campaign_Date": "2020-06-30", "Another_Date": "2020-07-01"}, {"Id": "125 ", "Campaign_Date": "2020-07-01", "Another_Date": "2020-07-01"}]

我尝试了以下方法:

for my_dict in my_dicts:
    for key in my_dict.items():
        campaign_key = 'Campaign_Date'
        if key == campaign_key:
            if value == "":
                value = value["Another_Date"] 
        else:
            continue

Answer 1

以防万一，如果您不想更新原始词典，同时对新词典进行必要的更正。

import copy
#my_dicts = [{"Id": "123", "Campaign_Date": "2020-06-30", "Another_Date": "2020-07-01"}, {"Id": "125", "Campaign_Date": "", "Another_Date": "2020-07-01"}]
# New input
my_dicts = [{"Id": "123", "Campaign_Date": "2020-06-30", "Another_Date": "2020-07-01"}, {"Id": "125", "Campaign_Date": "", "Another_Date": "2020-07-01"}, {"Id": "126", "Another_Date": "2020-07-01"}]

my_new_list = copy.deepcopy(my_dicts)

campaign_key = 'Campaign_Date'
for index, my_dict in enumerate(my_new_list):
    # check if "campaign_key" key exists
    if campaign_key in my_dict.keys():
        # Check for empty or null value for key "campaign_key"
        if my_dict[campaign_key] in ["", None]:
            my_dict['Campaign_Date'] = my_dict["Another_Date"]
    else:
        # if key "campaign_key" doesn't exist delete that item from list
        my_new_list.pop(index)

print(my_dicts)
print(my_new_list)
expected_output = [{'Id': '123', 'Campaign_Date': '2020-06-30', 'Another_Date': '2020-07-01'}, {'Id': '125', 'Campaign_Date': '2020-07-01', 'Another_Date': '2020-07-01'}]
if my_new_list == expected_output:
    print("Success")

输出:

[{'Id': '123', 'Campaign_Date': '2020-06-30', 'Another_Date': '2020-07-01'}, {'Id': '125', 'Campaign_Date': '', 'Another_Date': '2020-07-01'}, {'Id': '126', 'Another_Date': '2020-07-01'}]
[{'Id': '123', 'Campaign_Date': '2020-06-30', 'Another_Date': '2020-07-01'}, {'Id': '125', 'Campaign_Date': '2020-07-01', 'Another_Date': '2020-07-01'}]
Success