import requests

url = "https://{FUSION HOST}/api/subscriptions"

payload = {
    "numberOfListenerThreads": 123,
    "maxRetries": 123,
    "initialPosition": "<string>",
    "contextProperties": {}
}
headers = {
    "Authorization": "Basic <encoded-value>",
    "Content-Type": "application/json"
}

response = requests.put(url, json=payload, headers=headers)

print(response.json())

[
  {
    "resource": "<string>",
    "topic": "<string>",
    "numberOfListenerThreads": 123,
    "maxRetries": 123,
    "initialPosition": "<string>",
    "contextProperties": {},
    "id": "<string>"
  }
]