Challenge 2: Invert a Dictionary — Possible Solution
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capitals = {"France": "Paris", "Japan": "Tokyo", "Italy": "Rome"}

inverted = {city: country for country, city in capitals.items()}

print(inverted)

Output:
{'Paris': 'France', 'Tokyo': 'Japan', 'Rome': 'Italy'}

WHY THIS WORKS AS AN ANSWER
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capitals.items() reuses the chapter's own .items() method to produce
(key, value) pairs — here (country, city) pairs like ("France",
"Paris") — which the comprehension unpacks directly in its for clause,
the same tuple-unpacking-in-a-loop-header idiom from the previous
chapter's coordinate example.

The dict comprehension {city: country for country, city in ...}
mirrors the {k: v for ...} pattern from this chapter's dict
comprehension section exactly, except the expression before the for
deliberately swaps the two names — city becomes the new key, country
becomes the new value — which is precisely what "inverting" a
dictionary means: keys and values trade places.

This only produces a clean, fully reversible result because the
original values ("Paris", "Tokyo", "Rome") are themselves unique; if
two countries shared the same capital, one entry would silently
overwrite the other in the inverted dictionary, since dictionary keys
must be unique.