Python django tastypie获取相关列总金额

鉴于下面来自tastypie的JSON结果，我想在check.payments_total处创建一个新值，该值等于付款总额（在本例中为44.00）。你知道怎么做吗？我完全被难住了。付款是支票表的联接外键

{
"objects": [
    {
        "check": {
            "id": "58a81b36-1ea6-403b-9902-a50cbd13cf2e",
            "number": 2,
            "payments": [
                {
                    "amount": "5.00",
                },
                {
                    "amount": "39.00",
                }
            ]
        }
    }
]
}

---

如果用于响应，则可以重写资源中的以下方法（代码段来自

tastype.resources.resource

）：

只是包含一些（如未经测试，考虑为伪代码）：

---

你应该这样做。

你想在回复中获得付款总额还是DB中的所有付款总额？我想：对于回复，信息就这么多了。我会尽快实施这一计划，并让你知道进展如何。

def alter_list_data_to_serialize(self, request, data):
    """
    A hook to alter list data just before it gets serialized & sent to the user.

    Useful for restructuring/renaming aspects of the what's going to be
    sent.

    Should accommodate for a list of objects, generally also including
    meta data.
    """
    return data

 total_amount = 0.0
 for object in data[ 'objects' ]:
     total_amount += object[ 'amount' ]

 return { 'objects' : data[ 'objects' ], 'total_amount' : total_amount }