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: synchronization.rs
    path of file: ./repos/rust-raspberrypi-OS-tutorials/05_drivers_gpio_uart/src
    
    the code of the file until where you have to start completion: // SPDX-License-Identifier: MIT OR Apache-2.0
//
// Copyright (c) 2020-2023 Andre Richter <andre.o.richter@gmail.com>

//! Synchronization primitives.
//!
//! # Resources
//!
//!   - <https://doc.rust-lang.org/book/ch16-04-extensible-concurrenc
    
    fn lock<'a, R>(&'a self, f: impl FnOnce(&'a mut Self::Data) -> R) -> R {
        // In a real lock, there would be code encapsulating this line that ensures that this
        // mutable reference will ever only be given out once at a time.
        let data = unsafe { &mut *self.data.get() };

        f(data)
    }