Python Coding challenge - Day 711| What is the output of the following Python Code?

 

Code Explanation:

1) from dataclasses import dataclass

Imports the dataclass decorator.

@dataclass auto-generates common methods for a class (e.g., __init__, __repr__, __eq__) from its fields.

2) @dataclass(slots=True)

Converts the following class into a dataclass and enables __slots__.

slots=True means the class will define __slots__ = ('x', 'y'), which:

Prevents creation of a per-instance __dict__ (memory-efficient).

Disallows adding new attributes dynamically (e.g., p.z = 3 would raise AttributeError).

Can make attribute access slightly faster.

3) class Point:

Declares a simple data container named Point.

4) x: int and y: int

Declare two dataclass fields: x and y, both annotated as int.

Type hints are for readability/type checkers; they’re not enforced at runtime by default.

5) Auto-generated __init__

Because of @dataclass, Python effectively creates:

def __init__(self, x: int, y: int):

    self.x = x

    self.y = y

No need to write the constructor yourself.

6) p = Point(1, 2)

Instantiates Point using the generated __init__.

Sets p.x = 1 and p.y = 2.

7) Auto-generated __repr__

@dataclass also generates a readable string representation, roughly:

def __repr__(self):

    return f"Point(x={self.x}, y={self.y})"

8) print(p)

Prints the instance using that auto-generated __repr__.

Output

Point(x=1, y=2)

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