Python Interview questions - comprehensions
(Python version 3.9 or later version)
Which of the following Python objects is immutable?
set
dict
list
str
What would be the result of executing the following code? 
print(True*2)
TrueTrue
True True
2
Syntax Error
Python Interview Questions
  • Python - Comprehensions
    1. What will be the output of the following Python code snippet?

    k = [print(i) for i in my_string if i not in "aeiou"]

    A) prints all the vowels in my_string
    B) prints all the consonants in my_string
    C) prints all characters of my_string that aren’t vowels
    D) prints only on executing print(k)

    Answer: prints all characters of my_string that aren’t vowels

    Explanation: print(i) is executed if the given character is not a vowel.
    2. What will be the output of the following Python code snippet?

    k = [print(i) for i in my_string if i not in "aeiou"]
    print(k)

    A) all characters of my_string that aren’t vowels
    B) a list of Nones
    C) List of Trues
    D) List of Falses

    Answer: a list of Nones

    Explanation: print() returns None.
    3. What will be the output of the following Python code snippet?

    my_string = "hello world"
    k = [(i.upper(), len(i)) for i in my_string]
    print(k)

    A) [(‘HELLO’, 5), (‘WORLD’, 5)]
    B) [(‘H’, 1), (‘E’, 1), (‘L’, 1), (‘L’, 1), (‘O’, 1), (‘ ‘, 1), (‘W’, 1), (‘O’, 1), (‘R’, 1), (‘L’, 1), (‘D’, 1)]
    C) [(‘HELLO WORLD’, 11)]
    D) none of the mentioned

    Answer: [(‘H’, 1), (‘E’, 1), (‘L’, 1), (‘L’, 1), (‘O’, 1), (‘ ‘, 1), (‘W’, 1), (‘O’, 1), (‘R’, 1), (‘L’, 1), (‘D’, 1)]

    Explanation: We are iterating over each letter in the string.
    4. What will be the output of the following Python code snippet?

    x = [i**+1 for i in range(3)]; print(x);

    A) [0, 1, 2]
    B) [1, 2, 5]
    C) error, **+ is not a valid operator
    D) error, ‘;’ is not allowed

    Answer: [0, 1, 2]

    Explanation: **+1 is evaluated as (i)**(+1).
    5. What will be the output of the following Python code snippet?

    print([i.lower() for i in "HELLO"])

    A) [‘h’, ‘e’, ‘l’, ‘l’, ‘o’]
    B) ‘hello’
    C) [‘hello’]
    D) hello

    Answer: [‘h’, ‘e’, ‘l’, ‘l’, ‘o’]

    Explanation: We are iterating over each letter in the string.
    6. What will be the output of the following Python code snippet?

    print([i+j for i in "abc" for j in "def"])

    A) [‘da’, ‘ea’, ‘fa’, ‘db’, ‘eb’, ‘fb’, ‘dc’, ‘ec’, ‘fc’]
    B) [[‘ad’, ‘bd’, ‘cd’], [‘ae’, ‘be’, ‘ce’], [‘af’, ‘bf’, ‘cf’]]
    C) [[‘da’, ‘db’, ‘dc’], [‘ea’, ‘eb’, ‘ec’], [‘fa’, ‘fb’, ‘fc’]]
    D) [‘ad’, ‘ae’, ‘af’, ‘bd’, ‘be’, ‘bf’, ‘cd’, ‘ce’, ‘cf’]

    Answer: [‘ad’, ‘ae’, ‘af’, ‘bd’, ‘be’, ‘bf’, ‘cd’, ‘ce’, ‘cf’]

    Explanation: Explanation: If it were to be executed as a nested for loop, i would be the outer loop and j the inner loop.
    7. What will be the output of the following Python code snippet?

    print([[i+j for i in "abc"] for j in "def"])

    A) [‘da’, ‘ea’, ‘fa’, ‘db’, ‘eb’, ‘fb’, ‘dc’, ‘ec’, ‘fc’]
    B) [[‘ad’, ‘bd’, ‘cd’], [‘ae’, ‘be’, ‘ce’], [‘af’, ‘bf’, ‘cf’]]
    C) [[‘da’, ‘db’, ‘dc’], [‘ea’, ‘eb’, ‘ec’], [‘fa’, ‘fb’, ‘fc’]]
    D) [‘ad’, ‘ae’, ‘af’, ‘bd’, ‘be’, ‘bf’, ‘cd’, ‘ce’, ‘cf’]

    Answer: [[‘ad’, ‘bd’, ‘cd’], [‘ae’, ‘be’, ‘ce’], [‘af’, ‘bf’, ‘cf’]]

    Explanation: The inner list is generated once for each value of j.
    8. What will be the output of the following Python code snippet?

    print([if i%2==0: i; else: i+1; for i in range(4)])

    A) [0, 2, 2, 4]
    B) [1, 1, 3, 3]
    C) error
    D) none of the mentioned

    Answer: error

    Explanation: Syntax error.
    9. Which of the following is the same as list(map(lambda x: x**-1, [1, 2, 3]))?
    A) [x**-1 for x in [(1, 2, 3)]]
    B) [1/x for x in [(1, 2, 3)]]
    C) error
    D) [1/x for x in (1, 2, 3)]

    Answer: [1/x for x in (1, 2, 3)]

    Explanation: x**-1 is evaluated as (x)**(-1).
    • gk