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: rpc_client.rs
    path of file: ./repos/solana/rpc-client/src/nonblocking
    
    the code of the file until where you have to start completion: //! Communication with a Solana node over RPC asynchronously .
//!
//! Software that interacts with the Solana bloc
    
    pub async fn get_recent_blockhash(&self) -> ClientResult<(Hash, FeeCalculator)> {
        #[allow(deprecated)]
        let (blockhash, fee_calculator, _last_valid_slot) = self
            .get_recent_blockhash_with_commitment(self.commitment())
            .await?
            .value;
        Ok((blockhash, fee_calculator))
    }