Exercise 7: One Level Too Deep — Possible Solution
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order = {
    "id": 5012,
    "customer": "Dana",
    "items": ["pen", "ink"],
    "delivery": {"city": "Leith", "notes": ["ring bell", "fragile"], "fee": 3.5},
}

for key, value in order.items():
    if isinstance(value, list):
        print(f"{key}: {', '.join(map(str, value))}")          # copy 1
    elif isinstance(value, dict):
        print(f"{key}:")
        for inner_key, inner_value in value.items():
            if isinstance(inner_value, list):
                print(f"  {inner_key}: {', '.join(map(str, inner_value))}")   # copy 2
            else:
                print(f"  {inner_key}: {inner_value}")
    else:
        print(f"{key}: {value}")

# Two copies of the list handling. A third level of nesting would need a third.

Output:
id: 5012
customer: Dana
items: pen, ink
delivery:
  city: Leith
  notes: ring bell, fragile
  fee: 3.5

WHY THIS WORKS AS AN ANSWER
------------------------------
The list branch had to be written twice: once at the top level and
once inside the inner loop, because the inner loop only knows what
you tell it. A dictionary nested one level deeper would need the
chain written a third time inside that, and so on, and you would
have to know the maximum depth in advance. That is the real limit of
the inline approach and the strongest argument for the function in
the lesson: a function that calls itself for each inner dictionary
copes with any depth from a single copy of the code. Use this
exercise as the practical example for the function discussion.