- `public_key` (string) - This is the UCloud public key. It must be provided unless `profile` is set, but it can also be sourced from the `UCLOUD_PUBLIC_KEY` environment variable. - `private_key` (string) - This is the UCloud private key. It must be provided unless `profile` is set, but it can also be sourced from the `UCLOUD_PRIVATE_KEY` environment variable. - `region` (string) - This is the UCloud region. It must be provided, but it can also be sourced from the `UCLOUD_REGION` environment variables. - `project_id` (string) - This is the UCloud project id. It must be provided, but it can also be sourced from the `UCLOUD_PROJECT_ID` environment variables.