python - 使用通用键值对对字典列表中的值求和

Question

如何对字典列表中的重复元素求和？

sample list :

data = [
        [
            {'user': 1, 'rating': 0},
            {'user': 2, 'rating': 10},
            {'user': 1, 'rating': 20},
            {'user': 3, 'rating': 10}
        ],
        [
            {'user': 4, 'rating': 4},
            {'user': 2, 'rating': 80},
            {'user': 1, 'rating': 20},
            {'user': 1, 'rating': 10}
        ],
    ]

预期输出:

op = [
        [
            {'user': 1, 'rating': 20},
            {'user': 2, 'rating': 10},
            {'user': 3, 'rating': 10}
        ],
        [
            {'user': 4, 'rating': 4},
            {'user': 2, 'rating': 80},
            {'user': 1, 'rating': 30},
        ],
    ]

Answer 1

与 pandas :

>>> import pandas as pd
>>> [pd.DataFrame(dicts).groupby('user', as_index=False, sort=False).sum().to_dict(orient='records') for dicts in data]
[[{'user': 1, 'rating': 20},
  {'user': 2, 'rating': 10},
  {'user': 3, 'rating': 10}],
 [{'user': 4, 'rating': 4},
  {'user': 2, 'rating': 80},
  {'user': 1, 'rating': 30}]]