from itertools import groupby

需求：期望由 a 得到 b

实现方法：

from itertools import groupby


a = [
    {'name': 'a', 'value': 1}, 
    {'name': 'b', 'value': 1},
    {'name': 'a', 'value': 2},
]

b = [['a', 'b'], ['a']]

lst = []

for key, group in groupby(a, key=lambda x: x['value']):
    lst.append([item['name'] for item in group])

print(lst)