What does the `len()` function return when called on the Python dictionary `d = {'a': 1, 'b': 2, 'c': 3}`?
Answer and explanation
Correct answer: B. 3
- Step 1: The built-in `len()` function on a dictionary returns the number of key-value pairs stored in it.
- Step 2: The dictionary has three distinct keys (`'a'`, `'b'`, `'c'`), so `len(d)` evaluates to 3.
Answer
3.
Why not the others: '6' counts keys and values separately; '1' returns the first key's value; 'Error' assumes dictionaries have no length property.
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