- `access_key` (string) - This is the Alicloud access key. It must be provided, but it can also be sourced from the ALICLOUD_ACCESS_KEY environment variable. - `secret_key` (string) - This is the Alicloud secret key. It must be provided, but it can also be sourced from the ALICLOUD_SECRET_KEY environment variable. - `region` (string) - This is the Alicloud region. It must be provided, but it can also be sourced from the ALICLOUD_REGION environment variables.