Python Variable and Datatype Quiz

Which of the following is a valid Python variable name?

• 2variable

• variable_2

• @variable

• var-iable

Answer explanation

Variable names can't start with a number or use special characters like @ or -)

What will be the output of the following code?

• int

• float

• complex

• none

Answer explanation

The addition of an int and float results in a float

Which of these data types is immutable?

• List

• Set

• Dictionary

• Tuple

Answer explanation

Tuples are immutable, while lists, dictionaries, and sets are mutable

A single-element tuple requires a trailing comma, like (5,)

• tuple = (5)

• tuple = 5

• tuple = (5,)

• tuple = [5]

Answer explanation

A single-element tuple requires a trailing comma, like (5,)

Which of the following statements creates an empty set in Python?

• set1 = {}

• set1 = set()

• set1 = []

• set1 = emptyset{}

Answer explanation

Using set() creates an empty set, whereas {} creates an empty dictionary

What will be the output of the following code?

• 3

• 4

• 5

• 6

Answer explanation

Appending a list inside another list counts as one additional element, so the length is 4

What will the following code output?

• Pyt

• Pyth

• Py

• Python

Answer explanation

Slicing x[0:3] returns the substring 'Pyt'

Which of these Python collections is unordered?

• List

• Tuple

• Set

• String

Answer explanation

Sets are unordered collections, while lists, tuples, and strings are ordered

What will be the output of the following code?

• {1, 2, 3, 4}

• {3, 1, 2, 3, 4}

• {1, 2, 3, 3, 4}

• An error will occur

Answer explanation

Sets do not allow duplicate elements, so {1, 2, 3, 4, 5} is the result

Which of the following data types can hold duplicate values?

• Set

• Tuple

• Dictionary

• None of the above

Answer explanation

Tuples, like lists, can contain duplicate values; sets and dictionary keys do not allow duplicates