Challenge 2: A Printable Fraction Class — Possible Solution
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class Fraction:
    def __init__(self, numerator, denominator):
        self.numerator = numerator
        self.denominator = denominator

    def __str__(self):
        return f"{self.numerator}/{self.denominator}"

half = Fraction(3, 4)
print(half)

Output:
3/4

WHY THIS WORKS AS AN ANSWER
------------------------------
__init__(self, numerator, denominator) reuses the plain
instance-attribute pattern from Chapter 1 — self.numerator and
self.denominator are set directly from the constructor's arguments,
nothing new here.

__str__(self) reuses this chapter's own Point class example exactly:
defining a method with that specific dunder name teaches Python what
string to produce whenever the object is passed to print() (or str()).
Without it, print(half) would fall back to the default, unhelpful
"<__main__.Fraction object at 0x...>" representation the chapter
described.

The f-string f"{self.numerator}/{self.denominator}" inside __str__
reuses ordinary f-string formatting from Course 1, just applied to two
instance attributes instead of local variables — building the
"3/4"-style string the challenge asks for. print(half) then
automatically calls __str__ behind the scenes and prints its return
value, with no explicit .toString()-style call needed at the call
site.