Python Data Types and Variables Questions and Answers — Questions and Answers

Question 1: Which of the following data types is immutable in Python?

list
dict
set
tuple (Correct answer)

Correct answer: tuple

In Python, immutable data types are those that cannot be changed after they are created. Tuples, defined with parentheses, are immutable. Once a tuple is created, its elements cannot be altered, added, or removed. Lists, dictionaries, and sets are all mutable, meaning their contents can be changed after creation.

Question 2: What will be the output of the following Python code? x = 5 y = '10' print(x + int(y))

"510"
15 (Correct answer)
TypeError
10

Correct answer: 15

The code first initializes an integer variable `x` to 5 and a string variable `y` to '10'. The `int()` function is used for type casting, converting the string '10' into the integer 10. Then, the addition operation `x + 10` is performed, which results in `5 + 10 = 15`. The `print()` function then outputs this result.

Question 3: A programmer is creating a script to store user configurations that should not change during program execution. Which data type is most appropriate for storing a collection of these configuration settings?

list
tuple (Correct answer)
dictionary
set

Correct answer: tuple

A tuple is the most appropriate choice because it is an immutable data type. This means that once the configuration settings are stored in a tuple, they are protected from accidental modification during the program's execution, ensuring data integrity.

Question 4: Which of the following is an invalid variable name in Python?

_my_var
myVar2
2myVar (Correct answer)
MYVAR

Correct answer: 2myVar

Python variable names must start with a letter (a-z, A-Z) or an underscore (_). They cannot begin with a digit. Therefore, '2myVar' is an invalid variable name. '_my_var', 'myVar2', and 'MYVAR' are all valid.

Question 5: Consider the following code snippet: def my_func(): x = 10 print(x) x = 20 my_func() print(x)

10 20 (Correct answer)
20 10
10 10
20 20

Correct answer: 10 20

This question tests understanding of variable scope. The `x = 20` assignment creates a global variable. Inside `my_func()`, `x = 10` creates a new local variable `x` that shadows the global one. The `print(x)` inside the function prints the local `x` (10). After the function call, the `print(x)` in the global scope prints the global `x` (20).

Question 6: What is the data type of the result of the expression `10 / 4`?

int
float (Correct answer)
tuple
str

Correct answer: float

In Python 3, the standard division operator `/` always performs float division, meaning the result will be a float even if the numbers divide evenly. `10 / 4` results in `2.5`, which is a float data type. Integer division is performed with the `//` operator.

Python Data Types and Variables Questions and Answers

Which of the following data types is immutable in Python?