python dict 相同key 合并value的实例

如下所示：

# #### dict中将key相同的字典合并在一个对象里
"""
a = {"a": 1, "b": 2, "c": 1}
for k, v in a.iteritems():
 tmp.setdefault(v, []).append(k)
"""
tmp = {}
objs = OnlineScoringTeacher.objects.filter(
 entry__message_ila__id=1038,
 teacher=1,
).select_related('entry')
# 常规方法
for obj in objs:
 if obj.entry.subject_id not in tmp:
   tmp.update({
     obj.entry.subject_id: []
   })
 tmp[obj.entry.subject_id].append(obj)
# 法二
for obj in objs:
 tmp.setdefault(obj.entry.subject_id, []).append(obj)

来源：https://blog.csdn.net/YangHeng816/article/details/79142754