"""Solution 6.1.5 — Method calls need parentheses

Chapter 6: Objects — Everyday Programming

Bug type: Logical

wheel.circumference refers to the method object instead of calling it,
so the printout is a function reference, not the number. Adding
parentheses — wheel.circumference() — calls the method and prints
62.8318.

Exercise: ex_6_1_5.py
"""

class Circle:
    def __init__(self, radius):
        self.radius = radius

    def circumference(self):
        return 2 * 3.14159 * self.radius

wheel = Circle(10)
print(wheel.circumference())   # 62.8318