A developer wants to create a 3x3 matrix where each cell contains the product of its row and column indices. They plan to use a nested list comprehension. Which code produces the correct matrix?

[i*j for i in range(3) for j in range(3)]

[[i*j for j in range(3)] for i in range(3) if i*j > 0]

[[i*j for i in range(3)] for j in range(3)]

[[i*j for j in range(3)] for i in range(3)]

A developer needs to create a list of all possible combinations of two lists, but only where the sum of the two elements is greater than 10. They want to use a nested comprehension. Which code is correct?

[(x, y) for x in list1 for y in list2 if x + y > 10]

[(x, y) for x in list1 if x + y > 10 for y in list2]

[[(x, y) for x in list1] for y in list2 if x + y > 10]

[(x, y) for x in list1 for y in list2 if x + y > 10 and x > 0]

A QA engineer needs to extract all positive numbers from a list of integers, but only if the number is also a perfect square. They want a one-liner. Which comprehension achieves this?

[x for x in numbers if x > 0 and x**0.5 == int(x**0.5)]

[x for x in numbers if x > 0 and int(x**0.5)**2 == x]

[x for x in numbers if x > 0 and x % 2 == 0]

[x for x in numbers if x**0.5 % 1 == 0]

A data scientist has a list of lists, where each inner list contains strings. They want to create a single flat list of all strings that have length greater than 3. Which nested comprehension does this?

[[s for s in sublist if len(s) > 3] for sublist in list_of_lists]

[s for s in sublist for sublist in list_of_lists if len(s) > 3]

[s for sublist in list_of_lists for s in sublist if len(s) > 3]

[s for sublist in list_of_lists if len(s) > 3 for s in sublist]

A developer is building a list of all prime numbers between 10 and 50. They want to use a list comprehension with a helper function `is_prime(n)`. Which comprehension is correct?

[n for n in range(10, 51) if is_prime(n) and n % 2 == 0]

[n for n in range(10, 51) if is_prime(n)]

[n for n in range(10, 51) if not is_prime(n)]

[n for n in range(10, 50) if is_prime(n)]

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 4)

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 16–20

16application · medium
A developer wants to create a 3x3 matrix where each cell contains the product of its row and column indices. They plan to use a nested list comprehension. Which code produces the correct matrix?
Select an answer first
17expert · hard
A developer needs to create a list of all possible combinations of two lists, but only where the sum of the two elements is greater than 10. They want to use a nested comprehension. Which code is correct?
Select an answer first
18application · medium
A QA engineer needs to extract all positive numbers from a list of integers, but only if the number is also a perfect square. They want a one-liner. Which comprehension achieves this?
Select an answer first
19application · medium
A data scientist has a list of lists, where each inner list contains strings. They want to create a single flat list of all strings that have length greater than 3. Which nested comprehension does this?
Select an answer first
20application · medium
A developer is building a list of all prime numbers between 10 and 50. They want to use a list comprehension with a helper function `is_prime(n)`. Which comprehension is correct?
Select an answer first

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