Extending behaviour with inheritance

Beginner Python OOP Inheritance

Created by Pavel · 07.03.2026 at 19:57 UTC · 5.0 (1 ratings) · 9 completed

When several pipelines share the same storage shape but differ in what happens on each write, inheritance lets you reuse the boring parts and override the interesting hook. GrowingContainer keeps the parent's list semantics yet adds a visible trace each time a value arrives.

Always call super() when you still need the parent's invariant work; the edge case is bypassing it and silently dropping data appends.

University approvals: 0

Tasks

Question 1

Which syntax correctly declares that a class inherits from another?

Hint

Parent name goes in parentheses

class Child extends Parent

class Child inherits Parent

class Child(Parent):

class Child from Parent:

Question 2

Fill in GrowingContainer.add. DataContainer is already defined: __init__ sets self.name and self.data, and add appends to self.data. Override add so the parent still stores the value, then emit one line of the form Growing: <value> for the argument passed in (for example Growing: 42 when value is 42).

Grading: expression mode — your file is executed once; each test then evaluates one Python expression in that namespace (stdout or value as configured for the test).

Hint

Delegate with super().add(value) before printing; otherwise the list never grows.

class DataContainer:
    def __init__(self, name):
        self.name = name
        self.data = []

    def add(self, value):
        self.data.append(value)

class GrowingContainer(DataContainer):
    def add(self, value):
        # TODO

# DO NOT CHANGE THE CODE BELOW!
container = GrowingContainer("exp1")

Starter code is prefilled; replace TODO blocks with your solution.

Runtime output (stdout/stderr)

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Run checks runtime behavior only. Final correctness is evaluated when you submit.

Card Info

Topic: Python OOP Inheritance
Difficulty: Beginner
Rating: 5.0 / 5.0
Completed: 9 users

Creator

Pavel