Describe a circle
Input
describe_shape("circle", 2)
Output
Circle(radius=2)
Circle.describe() returns the radius formatted into the string.
Full lesson preview
Implement Polymorphic describe() Methods
Define polymorphic describe() methods for different shapes so code can treat them uniformly.
Python practice10 minInheritance & PolymorphismBeginnerLast updated April 8, 2026
Problem statement
You have a Shape base class with a describe() method intended to be overridden by subclasses. Implement two subclasses, Circle and Rectangle, each providing a describe() method returning a string that summarizes the shape and its dimensions.
Also implement describe_shape(shape_type, *dims) which constructs the appropriate shape object and returns its describe() string. For unknown shape_type, return the string 'Unknown shape'.
- For Circle, the describe string should be: "Circle(radius={radius})"
- For Rectangle, the describe string should be: "Rectangle(width={width},height={height})"
Task
Create subclasses that implement a common describe() interface so different shape objects can be described polymorphically.
Examples
Input format
A call to describe_shape(shape_type: str, *dimensions). For circle provide one dimension (radius). For rectangle provide two dimensions (width, height).
Output format
A single string describing the shape and its dimensions, or 'Unknown shape' for unsupported types.
Constraints
Do not use any external libraries. Dimensions may be integers or floats, including 0 or negative values for testing. shape_type is case-insensitive (treat 'Circle' and 'circle' the same).
Samples
Sample 1
Input
describe_shape("rectangle", 3, 4)
Output
Rectangle(width=3,height=4)
Rectangle.describe() combines width and height in the expected format.