Count number of times key appears in json

Hi,
Need help please in counting the number of times the key source appears in the file.

I need to change the names of the keys name and value so I need to know how many times to loop through the json file.

Below is a sample of the json file I received and one of the many things I tried.

with open(r’C:\Users\Administrator\Documents\rajson.json’) as f:
jsonObj = json.load(f)

print(jsonObj[1])

key_source = [k['data'] for k in jsonObj[1] if k.get('source')]
print('len: ', len(key_source))
{
   "timestamp": "2022-09-20T08:16:00.000Z",
   "metadata": {   
   "orgID": "6780",
   "projectId": 0988,
  }
 },
 {
  "data":  
   "workers": [      
    {
     "identifiers": { 
      "FullName": null,
      "NINumber": null,
      "CompID": null
     },
     "lastName": null,
     "costCenter": null
    },
    {
     "codes": [  
       {
       "source": {
        "name": "net_salary",
        "value": 11500
       },
       "name": "net_salary",
       "code": "rt_sa",
       "value": 11500
      },
 {
     "identifiers": {
      "FullName": null,
      "NINumber": null,
      "Comp ID": null
     },
     "lastName": null,
     "costCenter": null
    },
    {
     "codes": [
      {
       "source": {
        "name": "hiredate",
        "value": 3.333
       },
       "name": "hiredate",
       "code": "h_code",
       "value": 3.333
      },
Thank you