A developer is writing a function that checks whether a given key exists in a dictionary before accessing it. The developer wants to avoid a KeyError. Which code snippet correctly performs this check?

if key in config: value = config[key]

if config.has_key(key): value = config[key]

if config.get(key): value = config[key]

if key is in config: value = config[key]

Why can a tuple be used as a dictionary key, but a list cannot?

Tuples are smaller in memory, so they are allowed as keys.

Lists can contain duplicate elements, which would break dictionary keys.

Tuples are faster than lists, so they are preferred for keys.

Tuples are immutable, so they are hashable, while lists are mutable and unhashable.

GIAC Python Coder

Domain 1Objective 2

Data Structures GPYC Practice Questions (Page 4)

Part of the Python Fundamentals domain, which makes up ~43% of our current practice bank. GIAC (SANS) does not publish an official question count, but from its 120-minute exam (~50–80 total, ~22–34 in this domain), expect 4–7 from this objective — we provide 37 practice questions to prepare you well beyond it. (estimate)

37questions here

8free pages

12concepts

Questions 16–20

16application · medium
A developer is writing a function that checks whether a given key exists in a dictionary before accessing it. The developer wants to avoid a KeyError. Which code snippet correctly performs this check?
Select an answer first
17foundation · easy
Why can a tuple be used as a dictionary key, but a list cannot?
Select an answer first
18foundation · easy
What is the result of the following code? ```python nums = [3, 1, 2] nums.reverse() print(nums) ```
Select an answer first
19expert · hard
A DevOps engineer is writing a Python function that takes a dictionary of configuration parameters (which may contain nested lists and dictionaries) and returns a modified copy. The function must NOT alter the original configuration object. The engineer uses the copy module. Which approach guarantees that no nested mutable object in the original is modified?
Select an answer first
20foundation · easy
What does the dictionary method get() return when the key is not found and no default argument is provided?
Select an answer first

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Data Structures GPYC Practice Questions (Page 4)

Questions 16–20

A developer is writing a function that checks whether a given key exists in a dictionary before accessing it. The developer wants to avoid a KeyError. Which code snippet correctly performs this check?

Why can a tuple be used as a dictionary key, but a list cannot?

What is the result of the following code? ```python nums = [3, 1, 2] nums.reverse() print(nums) ```

What does the dictionary method get() return when the key is not found and no default argument is provided?

Keep studying — Python Fundamentals