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: varule.rs
    path of file: ./repos/icu4x/utils/zerovec/derive/src
    
    the code of the file until where you have to start completion: // This file is part of ICU4X. For terms of use, please see the file
// called LICENSE at the top level of the ICU4X source tree
// (online at: https://github.com/unicode-org/icu4x/
    
            unsafe fn from_byte_slice_unchecked(bytes: &[u8]) -> &Self {
                // just the unsized part
                #[allow(clippy::indexing_slicing)] // TODO explain
                let unsized_bytes = &bytes[#ule_size..];
                let unsized_ref = <#unsized_field as zerovec::ule::VarULE>::from_byte_slice_unchecked(unsized_bytes);
                // We should use the pointer metadata APIs here when they are stable: https://github.com/rust-lang/rust/issues/81513
                // For now we rely on all DST metadata being a usize to extract it via a fake slice pointer
                let (_ptr, metadata): (usize, usize) = ::core::mem::transmute(unsized_ref);
                let entire_struct_as_slice: *const [u8] = ::core::slice::from_raw_parts(bytes.as_ptr(), metadata);
                &*(entire_struct_as_slice as *const Self)
            }