How to use the open function in Python?

Serialization queues process tasks strictly sequentially, one after another. The next task does not start until the current one finishes.

Concurrent queues can execute multiple tasks in parallel. The start order is not guaranteed, but tasks from the same queue are executed in the order they were added. The completion order is also not guaranteed.

Feature	Serialized queues	Concurrent queues
Start order	Strictly sequential	In order of addition
Execution order	Strictly sequential	Parallel
Completion order	Strictly sequential	Not guaranteed
Data state	Easy to manage	Requires synchronization

Example creation:

// Serialized queue
let serialQueue = DispatchQueue(label: "com.example.mySerialQueue")

// Concurrent queue with QoS .userInitiated
let concurrentQueue = DispatchQueue(label: "com.example.myConcurrentQueue", attributes: .concurrent)
// Built-in global concurrent queue
let globalQueue = DispatchQueue.global(qos: .userInitiated)

Usage:

serialQueue.async {
    // Task 1
}
serialQueue.async {
    // Task 2 (starts after task 1 finishes)
}

concurrentQueue.async {
    // Task 1
}
concurrentQueue.async {
    // Task 2 (may start before task 1 finishes)
}