如何在python中添加两个dict的对应元素？

Question

I have two dicts of the following type:

dict1 = {
   "name1": {
        "quantity" : 23,
        "totalCost": 110.0
    }, ......
}
dict2 = {
   "name1": {
        "quantity" : 45,
        "totalCost": 70.0
    },
   "name2": {
        "quantity" : 60,
        "totalCost": 120.0
    }, ......
}

The two dicts CAN have the same dict values or different dict values, while "quantity" and "totalCost" are fixed parameters. I want my resultant dict to be the sum of the two as follows:

dict1 = {
   "name1": {
        "quantity" : 68,
        "totalCost": 180.0
    },
   "name2": {
        "quantity" : 60,
        "totalCost": 120.0
    }, ......
}

I could use two for loops but I'm finding it very hard to debug for a larger number of nested dicts. Is there an easier method that performs this update operation?

Answer 1

As "quantity" and "totalCost" are fixed keys of the inside dict, you can simply do this:

for k, v in dict2.items():
    if k not in dict1:
        dict1[k] = v
    else:
        dict1[k]["quantity"] += v["quantity"]
        dict1[k]["totalCost"] += v["totalCost"]