You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: example.rs
    path of file: ./repos/cerbos/docs/modules/policies/examples
    
    the code of the file until where you have to start completion: use cerbos::sdk::attr::{attr, StructVal};
use cerbos::sdk::model::{Principal, Resource, ResourceAction, ResourceList};
use cerbos::sdk::{CerbosAsyncClient, CerbosClientOptions, CerbosEndpoint, Result};

#[tokio::main]
async fn main() -> Result<()> {
    let opt =
        CerbosClientOptions::new(CerbosEndpoint::HostPort("localhost", 3593)).with_plaintext();
    let mut client = CerbosAsyncClient::new(opt).await?;

    let principal = Principal::new("123", ["USER"]).with_attributes([attr(
        "workspaces",
        StructVal([
            ("workspaceA", StructVal(
    
async fn main() -> Result<()> {
    let opt =
        CerbosClientOptions::new(CerbosEndpoint::HostPort("localhost", 3593)).with_plaintext();
    let mut client = CerbosAsyncClient::new(opt).await?;

    let principal = Principal::new("123", ["USER"]).with_attributes([attr(
        "workspaces",
        StructVal([
            ("workspaceA", StructVal([("role", "OWNER")])),
            ("workspaceB", StructVal([("role", "MEMBER")])),
        ]),
    )]);

    let actions: [&str; 2] = ["workspace:view", "pii:view"];

    let kind = "workspace";
    let resp = client
        .check_resources(
            principal,
            ResourceList::new_from([
                ResourceAction(Resource::new("workspaceA", kind), actions),
                ResourceAction(Resource::new("workspaceB", kind), actions),
            ]),
            None,
        )
        .await?;

    println!("{:?}", resp.response);

    Ok(())
}