What are some examples of annotations in Python 3.10?

What are some examples of annotations in Python 3.10?

In Python 3.10, annotations can be used to specify types for function parameters and return values. For example:

def greet(name: str) -> str:
    return f'Hello, {name}!'

Can you explain the benefits of using type annotations?

Type annotations improve code readability and help with static type checking, making it easier to catch errors before runtime.

Are there any new features in Python 3.10 related to annotations?

Yes, Python 3.10 introduced the | operator for union types, allowing you to write annotations like def func(param: int | str) -> None:.

How do I use annotations with custom classes?

You can annotate parameters and return types with custom classes just like built-in types. For example:

class Person:
    def __init__(self, name: str):
        self.name = name

def get_person() -> Person:
    return Person('Alice')