Writing Your First Function: From a Sentence to is_even

How do you turn a plain English sentence into a working def — and why can the whole if/else collapse into a single returned Boolean?

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

Translate the sentence into a function

Here is the English task: "Given a whole number, tell me whether it is even." Turn it into a function named is_even with a single parameter that returns True when the number is even and False otherwise. A short docstring is filled in for you.

Hint: % gives the remainder after division, and == tests equality and produces a Boolean.

def is_even(i):
    """Return True if i is even, False otherwise."""
    ...  # your code here — return True when i is even, False otherwise

def is_even(i):
    """Return True if i is even, False otherwise."""
    ...  # your code here — return True when i is even, False otherwise

Python runs in your browser

⌘/Ctrl + Enter runs

is a function defined with def

returns True or False, not a number

answers correctly for even, odd and zero

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