Writing Anonymous Functions With Lambda

Why can a one-line helper like is_even be rewritten as `lambda x: x % 2 == 0` — with no name and no `return` — and when is that actually worth doing?

Finger exercises

Short drills on what this video just taught. Write the code, run the checks, and reveal the answer only if you are stuck.

0 / 5 passed

Exercise 1 of 5

Square it with a lambda

Create an anonymous (lambda) function that takes one number and returns that number multiplied by itself. Do not use def and do not give the function a name of its own — write it as a lambda and assign that lambda to square.

# Build an anonymous function that returns the square of its input.
square = ...  # your code here — assign your lambda to this variable

# Build an anonymous function that returns the square of its input.
square = ...  # your code here — assign your lambda to this variable

Python runs in your browser

⌘/Ctrl + Enter runs

is a function you can call

squares the number it is given

handles zero

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