python3 urllib3 PoolManager.requests gives unexpected keyword 'json'

I'm building a Lambda in AWS, using python3, urllib3 and PoolManager.request()

My code:

def process_message(token, message):
    try:
        bucket_name = message['s3']['bucket']['name']
        object_name = message['s3']['object']['key']
        print(f"|---> Processing message {bucket_name}: {object_name}")
        # build request json
        req_json = { 'Bucket': bucket_name, 'Object': object_name }
        http = urllib3.PoolManager()
        bearer_token = "Bearer " + token
        auth_hdr = {'Authorization': bearer_token }
        ct_hdr = {'Content-Type': 'application/json'}
        obj_request_headers = {**auth_hdr, **ct_hdr}

        new_object_response = http.request('POST', oracle_notifier_listener_url, json = req_json, headers = obj_request_headers)
        logger.debug("Got new_object response: %s", new_object_response)

    except Exception as err:
        print("*---> An error occurred processing new object notification")
        raise err

I get the error:

{
  "errorMessage": "HTTPResponse.__init__() got an unexpected keyword argument 'json'",
  "errorType": "TypeError",
  "requestId": "8d6c5511-6ca6-4245-8042-3aa5b3b98f89",
  "stackTrace": [
    "  File \"/var/task/lambda_function.py\", line 23, in lambda_handler\n        process_message(token, message)\n",
    "  File \"/var/task/lambda_function.py\", line 107, in process_message\n    raise err\n",
    "  File \"/var/task/lambda_function.py\", line 102, in process_message\n        new_object_response = http.request('POST', oracle_notifier_listener_url, json = req_json, headers = obj_request_headers)\n",

What's weird is, the request seems to go through just fine, I can see in the logs a 202 response status:

[DEBUG] 2024-10-15T17:05:11.150Z    8d6c5511-6ca6-4245-8042-3aa5b3b98f89    Starting new HTTPS connection (1): endpt.com:443
[DEBUG] 2024-10-15T17:05:12.375Z    8d6c5511-6ca6-4245-8042-3aa5b3b98f89    https://endpt:443 "POST /path/to/getObject HTTP/1.1" 202 None

I also tried:

    new_object_response = http.request('POST', oracle_notifier_listener_url, json = json.dumps(req_json), headers = obj_request_headers)

I got the same response, same error.

FWIW, I'm using these docs: https://urllib3.readthedocs.io/en/stable/reference/urllib3.poolmanager.html

What am I doing wrong, oh great python devs worldwide?

This error indicates your urllib3 version is too old (1.x). The json keyword argument was new in urllib3 v2.

Upgrade urllib3.

If you can't upgrade due to some other constraints, you may have to modify the code for 1.x support. In the case of json requests, you can replace:

http.request("POST", ..., json=req_json)

with

http.request("POST", ..., body=json.dumps(req_json).encode())