Python Asyncio: Usage Guide

Asyncio is the standard library in Python used for writing asynchronous code. It offers a coroutine-based concurrency programming model, making it easier and more intuitive to write efficient asynchronous code.

With the Asyncio library, you can define coroutine functions, which are special functions that can pause execution when needed and resume later. This pausing and resuming operation is managed by Python’s event loop.

Here are some common uses of the Asyncio library:

1. A coroutine function is defined using the async def keyword, and it can contain the await keyword, which is used to pause execution and wait for another coroutine to complete.
2. Creating an event loop: Use the asyncio.get_event_loop() function to create an event loop object. The event loop is responsible for scheduling and running coroutine functions.
3. Run a coroutine: Run a coroutine using the loop.run_until_complete() method, which adds the coroutine to the event loop and runs it until completion.
4. Execute multiple coroutines concurrently: Using the asyncio.gather() function allows you to run multiple coroutines concurrently and wait for all of them to complete.
5. Asynchronous IO operations: By using the await keyword to call asynchronous IO operations, it is possible to perform non-blocking IO operations in coroutines, such as network requests, file read/write, and so on.
6. Timer: Using the asyncio.sleep() function, a timer can be added in a coroutine to achieve delayed execution of operations.
7. Callback function: a function can be registered as a callback function using the loop.call_soon() method, and it will be called when a specific event occurs.
8. Concurrently execute multiple tasks: You can use the asyncio.create_task() function to wrap a coroutine into a task, and then use the await keyword to wait for multiple tasks to complete simultaneously.

The above are just some basic usages of Asyncio, this library also offers more advanced features and tools to help with writing and managing asynchronous code more effectively.