assert — Easy Playground

Debugging aid that tests a condition and raises AssertionError if false

Python Playground

x = 10
assert x > 0, "x must be positive"
print("x is valid")

# Assert with expressions
name = "Alice"
assert len(name) > 0, "Name cannot be empty"
print(f"Name: {name}")

# Catching assertion errors
try:
    temperature = -300
    assert temperature > -273.15, f"Temperature {temperature} is below absolute zero"
except AssertionError as e:
    print(f"Invalid: {e}")

Output

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assert checks a condition and raises AssertionError if it's False. The message after the comma is optional but recommended.

Challenge

Try modifying the code above to explore different behaviors. Can you extend the example to handle a new use case?

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