authenticate.py

from google.oauth2 import service_account
from google.auth.transport.requests import Request
import json

def get_access_token():
    # Load service account credentials from JSON file or environment variable
    credentials = service_account.Credentials.from_service_account_info(
        json.loads('ACCOUNT_CREDS'),
        scopes=['https://www.googleapis.com/auth/cloud-platform']
    )
    
    # Refresh token if needed
    if credentials.expired:
        credentials.refresh(Request())
    
    return credentials.token