Dataclasses

Dataclasses are a special feature in Python that help you create classes used mainly for storing data.

They reduce boilerplate code by automatically generating common methods like:

• __init__()
• __repr__()
• __eq__()

Dataclasses were introduced in Python 3.7.

Why Use Dataclasses?

• Less code
• Cleaner syntax
• Automatic constructor creation
• Built-in comparison support
• Easy to read and maintain

Creating a Dataclass

To use dataclasses, import the dataclass decorator from the dataclasses module.

from dataclasses import dataclass@dataclass
class Student:
    name: str
    age: int
    marks: floats1 = Student("Hira", 22, 85.5)
print(s1)

Output:

Student(name='Hira', age=22, marks=85.5)

Notice:

• No need to write __init__()
• No need to write __str__()
• Everything is automatically created

Equality Comparison

Dataclasses automatically support comparison.

s1 = Student("Hira", 22, 85.5)
s2 = Student("Hira", 22, 85.5)print(s1 == s2)

Output:

True

Default Values

You can provide default values.

from dataclasses import dataclass@dataclass
class Student:
    name: str
    age: int = 18

Using field() for Advanced Options

The field() function allows customization.

from dataclasses import dataclass, field@dataclass
class Student:
    name: str
    age: int
    marks: float = field(default=0.0)

Frozen Dataclass (Immutable)

To make objects immutable:

from dataclasses import dataclass@dataclass(frozen=True)
class Student:
    name: str
    age: ints1 = Student("Hira", 22)

Now you cannot modify attributes.

Dataclass vs Normal Class

Normal Class
You manually write __init__()
More code
Manual comparison methods

Dataclass
Auto-generated methods
Less code
Built-in comparison

When to Use Dataclasses

• When class is mainly used to store data
• When you want clean and readable code
• When you need automatic comparison

Key Takeaway

Dataclasses simplify class creation for data storage.

They automatically generate important methods and make Python code cleaner, shorter, and easier to maintain.