"""Exercise 20.1.4 — Missing colon after def

Chapter 20: Common Pitfalls — Everyday Programming

This program should define a function that returns the area of a
rectangle and print it.

This program contains exactly one bug. Solution: sol_20_1_4.py
"""

def rectangle_area(width, height)
    return width * height

print(rectangle_area(4, 5))  # 20