Python Quiz

What will print([1, 2, 3] + [4, 5]) output?

• [1, 2, 3, 4, 5]

• [5, 4, 3, 2, 1]

• Error

• [1, 2, 3, [4, 5]]

Answer explanation

The + operator concatenates two lists.

Which of the following will create a shallow copy of a list a?

• b = a[:]

• b = a.copy()

• b = a[:]
  and
  b = a.copy()
  both options correct

• None of the above

Answer explanation

Both slicing and copy() create a shallow copy of the list.

What will print(len([[1, 2], [3, 4]])) return?

• 2

• 4

• 8

• Error

Answer explanation

The len() function returns the number of top-level elements, which is 2.

Which of the following will raise an error for tuple a?

• a = (1, 2)

• a[0] = 3

• len((1, 2, 3))

• (1, 2) + (3,)

Answer explanation

Tuples are immutable; modifying an element is not allowed.

What is the output of print((1, 2) * 2)?

• (1, 2, 1, 2)

• (1, 2, 2)

• Error

• [1, 2, 1, 2]

Answer explanation

The * operator repeats the tuple.

Which method is used to get the value associated with a key in a dictionary?

• value()

• get()

• key()

• items()

Answer explanation

The get() method retrieves the value for a given key.

What will print(len({1: "a", 2: "b"})) return?

• 1

• 2

• 3

• 4

Answer explanation

The len() function counts the number of key-value pairs.

What will print({}.get("key", "default")) output?

• None

• default

• key

• Error

Answer explanation

The get() method returns the default value if the key is not found.

Which of the following will raise an error?

• {1: "a", 2: "b"}[1]

• {1: "a", 2: "b"}["c"]

• {1: "a", 2: "b"}.get(3)

• {}

Answer explanation

Accessing a key not present in the dictionary raises a KeyError.

What will print({1, 2, 3} | {3, 4, 5}) output?

• Error

• {1, 2, 4, 5}

• {3}

• {1, 2, 3, 4, 5}

Answer explanation

The | operator performs a union of sets, combining unique elements from both sets.