A data engineer has a list of lists of numbers and wants to create a list of the sums of each inner list, but only for inner lists that have at least one even number. Which nested comprehension does this?

[sum(sublist) for sublist in list_of_lists if all(x % 2 == 0 for x in sublist)]

[sum(sublist) for sublist in list_of_lists if any(x % 2 == 0 for x in sublist) and len(sublist) > 2]

[sum(sublist) for sublist in list_of_lists if any(x % 2 == 0 for x in sublist)]

[sum(sublist) for sublist in list_of_lists if x % 2 == 0 for x in sublist]

A developer wants to create a list of all lowercase letters in a string, but only if they are vowels. They want a list comprehension. Which one is correct?

[c for c in text if c in 'aeiou']

[c for c in text if c.islower()]

[c for c in text if c.lower() in 'aeiou']

[c for c in text if c.islower() and c in 'aeiou']

A developer wants to create a list of all pairs (i, j) where i is from 1 to 3 and j is from 1 to 3, but only where i is less than j. They want a flat list of tuples. Which comprehension is correct?

[[(i, j) for i in range(1, 4)] for j in range(1, 4) if i < j]

[(i, j) for i in range(1, 4) for j in range(1, 4) if i < j]

[(i, j) for i in range(1, 4) for j in range(1, 4) if i > j]

[(i, j) for i in range(1, 4) if i < j for j in range(1, 4)]

A developer is refactoring a loop that builds a list of squares of even numbers from 0 to 100. They want to use a list comprehension, but they also need to ensure the code is as efficient as possible. Which comprehension is most efficient?

[x**2 for x in range(0, 101, 2)]

[x**2 for x in range(101) if x % 2 == 0]

[x**2 for x in range(101) if x % 2 == 0 and x % 4 == 0]

[x**2 for x in range(101) if not x % 2]

A developer needs to flatten a list of lists, but only include elements that are integers (not strings or floats). They also want to preserve the order. Which comprehension is correct and most efficient?

[x for sublist in list_of_lists if isinstance(x, int) for x in sublist]

[x for sublist in list_of_lists for x in sublist if isinstance(x, int)]

[x for x in sublist for sublist in list_of_lists if isinstance(x, int)]

[x for sublist in list_of_lists for x in sublist if type(x) == int]

Python InstitutePCAP - Certified Associate Python Programmer

Domain 5Objective 1

PCAP-31-03 5.1 Build Complex Lists Using List Comprehensions PCAP-31 Practice Questions (Page 2)

Part of the Miscellaneous (List Comprehensions, Lambdas, Closures, I/O) domain, which accounts for 22% of the PCAP-31 exam. Python Institute does not publish an official question count, but from its 65-minute exam (~25–45 total, ~6–10 in this domain), expect 1–2 from this objective — we provide 43 practice questions to prepare you well beyond it. (estimate)

43questions here

9free pages

2concepts

22%of the exam

Questions 6–10

6application · medium
A data engineer has a list of lists of numbers and wants to create a list of the sums of each inner list, but only for inner lists that have at least one even number. Which nested comprehension does this?
Select an answer first
7application · medium
A developer wants to create a list of all lowercase letters in a string, but only if they are vowels. They want a list comprehension. Which one is correct?
Select an answer first
8application · medium
A developer wants to create a list of all pairs (i, j) where i is from 1 to 3 and j is from 1 to 3, but only where i is less than j. They want a flat list of tuples. Which comprehension is correct?
Select an answer first
9expert · hard
A developer is refactoring a loop that builds a list of squares of even numbers from 0 to 100. They want to use a list comprehension, but they also need to ensure the code is as efficient as possible. Which comprehension is most efficient?
Select an answer first
10expert · hard
A developer needs to flatten a list of lists, but only include elements that are integers (not strings or floats). They also want to preserve the order. Which comprehension is correct and most efficient?
Select an answer first

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