curl --request GET \
  --url https://qall.io/api/campaigns/{campaign_id}/leads \
  --header 'Authorization: Bearer <token>'

import requests

url = "https://qall.io/api/campaigns/{campaign_id}/leads"

headers = {"Authorization": "Bearer <token>"}

response = requests.get(url, headers=headers)

print(response.text)

{
  "detail": [
    {
      "loc": [
        "<string>"
      ],
      "msg": "<string>",
      "type": "<string>"
    }
  ]
}