对列表中字典key相同的value进行相加

Question

对列表中字典key相同的value进行相加

比如
score = [{'username': 'lx', 'score': 20}, {'username': 'lx', 'score': 10},{'username': 'zs', 'score': 10},{'username': 'zs', 'score': 20}]

结果
score = [{'username': 'lx', 'score': 30},,{'username': 'zs', 'score': 30}]

Answer 1

score = [{'username': 'lx', 'score': 20}, {'username': 'lx', 'score': 10},{'username': 'zs', 'score': 10},{'username': 'zs', 'score': 20}]

ret = {}
for s in score:
    ret[s['username']] = ret.get(s['username'], 0) + s['score']
score = []
for key, value in ret.items():
    item = {}
    item['username'] = key
    item['score'] = value
    score.append(item)
print(score)