Unable to attach binary files for Azure DevOps REST API

[isiddas]

I was trying to upload binary files using Azure DevOps REST API service.
reference: https://docs.microsoft.com/en-us/rest/api/azure/devops/wit/attachments/create?view=azure-devops-rest...
I was trying to upload "ATTACHMENT_TEST.zip" ref : https://drive.google.com/file/d/15Y3IS0BWoCaMo7kjt6t1ZCdHNH_PGT65/view?usp=sharing

Converted ATTACHMENT_TEST.zip to base64 UEsDBBQAAAAAALZIcVSXxhNiBAAAAAQAAAAIAAAAVEVTVC50eHRTSUREUEsBAhQAFAAAAAAAtkhxVJfGE2IEAAAABAAAAAgAAAAAAAAAAQAgAAAAAAAAAFRFU1QudHh0UEsFBgAAAAABAAEANgAAACoAAAAAAA==

Tried to add base64 as json in payload. The URL produced by the output is giving me invalid zip

Code
import requests
import json

url = "https://dev.azure.com/{Organization}/{ProjectName}/_apis/wit/attachments?uploadType=Simple&api-versi..."

payload = json.dumps("[UEsDBBQAAAAAALZIcVSXxhNiBAAAAAQAAAAIAAAAVEVTVC50eHRTSUREUEsBAhQAFAAAAAAAtkhxVJfGE2IEAAAABAAAAAgAAAAAAAAAAQAgAAAAAAAAAFRFU1QudHh0UEsFBgAAAAABAAEANgAAACoAAAAAAA==]")
headers = {
'Content-Type': 'application/json',
'Authorization': 'Basic $AuthKey',
'Cookie': 'VstsSession=%7B%22PersistentSessionId%22%3A%22fe6c3302-6671-4bfc-9cbe-0d33f145a31f%22%2C%22PendingAuthenticationSessionId%22%3A%2200000000-0000-0000-0000-000000000000%22%2C%22CurrentAuthenticationSessionId%22%3A%2200000000-0000-0000-0000-000000000000%22%2C%22SignInState%22%3A%7B%7D%7D'
}

response = requests.request("POST", url, headers=headers, data=payload)

print(response.text)