Python Practice 10/22

List comprehension rewrite

You've already used a list comprehension to filter a list (phase 4). This time you're starting from the other direction: the function below already works - it's a plain for loop that builds up a list with .append() - and your job is to rewrite its body as a single-line list comprehension that returns the exact same result.

A list comprehension can filter and transform in one expression: [expr for x in items if condition] computes expr for every x that passes condition, collecting the results into a new list - the loop, the if, and the .append() all folded into one line.

Your task: rewrite even_squares(n) below so its body is a single list comprehension instead of a for loop, still returning the square of every even number from 1 to n (inclusive), in order.

You'll practice:

Combining a transform and a filter in one list comprehension
Recognizing a loop-plus-append pattern that a comprehension replaces

# Rewrite even_squares(n) below as a one-line list comprehension -
# same result: the square of every even number from 1 to n, in order.
def even_squares(n):
    result = []
    for i in range(1, n + 1):
        if i % 2 == 0:
            result.append(i * i)
    return result