您可以根据本例在代码中指向您的服务帐户文件

def explicit():
    from google.cloud import storage

    # Explicitly use service account credentials by specifying the private key
    # file.
    storage_client = storage.Client.from_service_account_json(
        'service_account.json')

    # Make an authenticated API request
    buckets = list(storage_client.list_buckets())
    print(buckets)

你可以在这里的官方文档中找到它。