What are some examples of using dataclasses in Python?

What are some examples of using dataclasses in Python?

Dataclasses in Python are a way to create classes that are primarily used to store data. They automatically generate special methods like init() and repr(). For example, you can define a simple dataclass like this:

from dataclasses import dataclass

@dataclass
class Person:
    name: str
    age: int

This creates a Person class with name and age attributes.

Can you show me how to use default values in dataclasses?

Sure! You can set default values for fields in a dataclass like this:

from dataclasses import dataclass

@dataclass
class Person:
    name: str
    age: int = 30  # Default age is 30

Now, if you create a Person without specifying an age, it will default to 30.

What about using dataclasses with lists or other dataclasses?

You can definitely use lists or other dataclasses as fields. For example:

from dataclasses import dataclass
from typing import List

@dataclass
class Team:
    name: str
    members: List[Person]

This Team class can hold a list of Person instances as its members.

Are there any performance considerations when using dataclasses?

Dataclasses are generally efficient, but if you have a large number of instances or complex data structures, consider profiling your code. They do add some overhead compared to plain classes, but the benefits of readability and maintainability often outweigh this.