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: aes.rs
    path of file: ./repos/CYFS/src/component/cyfs-base/src/crypto
    
    the code of the file until where you have to start completion: use crate::*;

use aes::{Aes256, BlockCipher};
use block_modes::block_padding::Pkcs7;
use block_modes::{BlockMode, Cbc};
use generic_array::typenum::{marker_traits::Unsigned, U48, U8};
use generic_array::GenericArray;
use sha2::Digest;
use std::fmt;
use std::fmt::{Display, Formatter};
use std::hash::Hash;
use std::str::FromStr;

// aes key used to crypto data
#[derive(Clone, Eq, PartialEq)]
pub struct AesKey(GenericArray<u8, U48>);

impl std::fmt::Debug for AesKey {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "{}"
    
    pub fn inplace_decrypt(&self, inout: &mut [u8], in_len: usize) -> Result<usize, BuckyError> {
        // let iv: [u8;16] = [0;16];

        let key = self.0.as_slice();
        let cipher = Cbc::<Aes256, Pkcs7>::new_from_slices(&key[0..32], &key[32..]).unwrap();
        match cipher.decrypt(&mut inout[..in_len]) {
            Ok(buf) => Ok(buf.len()),
            Err(e) => {
                let msg = format!(
                    "AesKey::inplace_decrypt error, inout={}, in_len={}, {}",
                    inout.len(),
                    in_len,
                    e
                );
                error!("{}", msg);

                Err(BuckyError::new(BuckyErrorCode::OutOfLimit, msg))
            }
        }
    }