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: block.rs
    path of file: ./repos/mini-lsm/mini-lsm/src
    
    the code of the file until where you have to start completion: mod builder;
mod iterator;

pub use builder::BlockBuilder;
use bytes::{Buf, BufMut, Bytes};
pub use iterator::BlockIterator;

pub(crate) const SIZEOF_U16: usize = std::mem::size_of::<u16>();

/// A block is the smallest unit of read and caching in LSM tree
    
    pub fn decode(data: &[u8]) -> Self {
        // get number of elements in the block
        let entry_offsets_len = (&data[data.len() - SIZEOF_U16..]).get_u16() as usize;
        let data_end = data.len() - SIZEOF_U16 - entry_offsets_len * SIZEOF_U16;
        let offsets_raw = &data[data_end..data.len() - SIZEOF_U16];
        // get offset array
        let offsets = offsets_raw
            .chunks(SIZEOF_U16)
            .map(|mut x| x.get_u16())
            .collect();
        // retrieve data
        let data = data[0..data_end].to_vec();
        Self { data, offsets }
    }