Python - 访问JSON中的字段

Question

我无法访问我从JSON API获取的某些字段，如果用户是多个on_call策略的一部分，我在API中不知道如何访问第二个或更多策略。我目前的代码只是在网络团队政策下两次返回Bob Brown，而不是在网络团队和solarwinds测试下两次bob brown

JSON示例

{
    "users": [{
        "id": "PN8PIFR",
        "name": "Bob Brown",
        "user_url": "/users/PN8PIFR",
        "invitation_sent": false,
        "marketing_opt_out": false,
        "on_call": [{
            "level": 2,
            "start": "2016-05-30T08:00:00Z",
            "end": "2016-06-06T08:00:00Z",
            "escalation_policy": {
                "id": "PYZTEI3",
                "name": "Network Team"
            }
        }, {
            "level": 1,
            "start": null,
            "end": null,
            "escalation_policy": {
                "id": "P3CBIDO",
                "name": "Solarwinds Test"
            }
        }],
        "job_title": "Network Engineer"
    }, {
        "id": "PLIMHAI",
        "name": "Bill Blue",
        "user_url": "/users/PLIMHAI",
        "invitation_sent": false,
        "marketing_opt_out": false,
        "on_call": [{
            "level": 1,
            "start": "2016-06-02T08:00:00Z",
            "end": "2016-06-03T06:00:00Z",
            "escalation_policy": {
                "id": "PARVPQB",
                "name": "DBA Team"
            }
        }],
        "job_title": "Database Administrator"
    }],
    "active_account_users": 9,
    "limit": 25,
    "offset": 0,
    "total": 6
}

view.py

class User(object):
    __attrs = ['PolicyID','Level','LevelNo', 'StartDate', 'EndDate', 'StartTime',
               'EndTime', 'Name', 'Mobile']

    def __init__(self, **kwargs):
        for attr in self.__attrs:
            setattr(self, attr, kwargs.get(attr, None))

    def __repr__(self):
        return ', '.join(
            ['%s: %r' % (attr, getattr(self, attr)) for attr in self.__attrs])          




### Get the Policy data ###
objPolicyData = getuser_data()
pdUsers = pdUser.objects.all()

### Index View ###
@login_required
def index(request):
    OnCallData = [] 
    for user_item_data in objPolicyData['users']:   
        user_data = User()     
        #get the user object from DB
        model_pd_user       = pdUser.objects.get(PagerDutyID=user_item_data['id'])
        user_data.Name   = model_pd_user.Name
        user_data.Mobile = model_pd_user.Mobile
        for on_call_data in user_item_data['on_call']:    
            user_data.LevelNo         = on_call_data['level']
            user_data.Level           = getLevel(on_call_data['level'])
            user_data.StartDate       = getDate(on_call_data['start'])
            user_data.EndDate         = getDate(on_call_data['end'])
            user_data.StartTime       = getTime(on_call_data['start'])
            user_data.EndTime         = getTime(on_call_data['end'])    
            user_data.PolicyID    = on_call_data['escalation_policy']['id']
            OnCallData.append(user_data)