Async/Await is a modern syntax introduced in Python 3.5 and later, designed to make working with asynchronous code much cleaner and easier to read. It utilizes the concept of coroutines – functions that can be paused and resumed later – to handle asynchronous operations without the complexity of callbacks or promises.
Traditionally, asynchronous programming involved callbacks, which could lead to "callback hell" – deeply nested functions that are difficult to understand and maintain. Async/Await provides a more readable and maintainable approach by allowing you to write asynchronous code that looks and behaves like synchronous code.
Async/Await is built on top of the concept of coroutines. A coroutine is a special type of function that can be paused and resumed. When a coroutine encounters an awaitable expression (like a future or a task), it pauses execution and yields control back to the event loop. The event loop can then handle other tasks while the awaited operation is running. Once the operation is complete, the coroutine resumes execution from where it left off.
The async keyword is used to define a coroutine function. The await keyword is used to pause the execution of the coroutine until an awaitable object completes. The asyncio library provides tools for working with coroutines and the event loop.
import asyncio
async def my_coroutine():
print("Starting coroutine")
await asyncio.sleep(2) # Simulate an asynchronous operation
print("Coroutine finished")
async def main():
await my_coroutine()
if __name__ == "__main__":
asyncio.run(main())