from justpaid import JustPaidAPIprint(justpaid.__version__) # Should print "0.x.x"# Initialize the API clientapi = JustPaidAPI(api_token="your_api_token_here")# Get billable items by customer_iditems = api.get_billable_items(customer_id="customer-123")# Or get billable items by external_customer_iditems = api.get_billable_items(external_customer_id="ext-customer-123")print(items)