const response = await fetch('https://service.pcibooking.net/api/accounts/authenticate/', {
  method: 'POST',
  headers: {
    'Authorization': 'APIKEY your-api-key'
  }
});

console.log(response.status); // 200 if valid

import requests

response = requests.post(
    'https://service.pcibooking.net/api/accounts/authenticate/',
    headers={
        'Authorization': 'APIKEY your-api-key'
    }
)

print(response.status_code)  # 200 if valid

// Empty body. The API key is valid and the service is available.

{
    "code": -1003,
    "message": "Not authorized to access this resource",
    "moreInfo": "Bad or missing authorization data, expected APIKEY",
    "errorList": null
}