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: aws_signing_vault.rs
    path of file: ./repos/ockam/implementations/rust/ockam/ockam_vault_aws/src
    
    the code of the file until where you have to start completion: use crate::aws_kms_client::{AwsKmsClient, AwsKmsConfig, KmsClient};
use crate::error::Error;
use ockam_core::compat::sync::{Arc, RwLock};
use ockam_core::{async_trait, Result};
use ocka
    
    pub async fn create_with_config(config: AwsKmsConfig) -> Result<Self> {
        let client = AwsKmsClient::new(config).await?;

        let mut key_pairs: Vec<AwsKeyPair> = vec![];
        // Fetch list of all keys, then fetch the public key for each key
        let keys = client.list_keys().await?;

        for key in keys {
            match client.public_key(&key).await {
                Ok(public_key) => key_pairs.push(AwsKeyPair { key, public_key }),
                // There are different possible causes here, but it's also possible that
                // the Key may in deletion pending state, or have a different key type.
                // Therefore, the best strategy is to just skip that key
                Err(err) => error!("Error exporting public key: {err}"),
            }
        }

        Ok(Self {
            client: Arc::new(client),
            keys: Arc::new(RwLock::new(key_pairs)),
        })
    }