Rust Platform

🎯 In Python, __str__ controls what users see when they print an object:

class Fraction:
    def __init__(self, num, den):
        self.num, self.den = num, den

    def __str__(self):
        return f"{self.num}/{self.den}"

print(Fraction(3, 4))  # 3/4

And __repr__ is for developers — what you see in the REPL or in debug output. Many Python developers conflate the two or only implement one.

Rust makes this separation explicit with two traits:

You met Debug in the previous exercise — it can be derived with …