PCAP Comprehensions and Iterators

Question 1

Which syntax creates a list comprehension in Python?

Accepted Answer

[x for x in range(5)]

Answer

{x for x in range(5)}

Answer

(x for x in range(5))

Answer

Question 2

What does a generator expression return compared to a list comprehension?

Accepted Answer

A lazy iterator evaluated on demand

Answer

A list evaluated immediately

Answer

A tuple

Answer

A set

Question 3

What is the result of `[x**2 for x in range(4)]`?

Accepted Answer

[0, 1, 4, 9]

Answer

[1, 4, 9, 16]

Answer

[0, 1, 2, 3]

Answer

[1, 2, 3, 4]

Question 4

How do you add a condition to a list comprehension to include only even numbers?

Accepted Answer

[x for x in range(10) if x%2==0]

Answer

[x if x%2==0 for x in range(10)]

Answer

[x for x%2==0 in range(10)]

Answer

[x for x in range(10) where x%2==0]

Question 5

Which syntax creates a dictionary comprehension?

Accepted Answer

{k:v for k,v in items}

Answer

[k:v for k,v in items]

Answer

(k:v for k,v in items)

Answer

dict(k:v for k,v in items)

Question 6

What does the `enumerate()` function return when iterating?

Accepted Answer

A tuple of (index, value)

Answer

Only the index

Answer

Only the value

Answer

A dictionary