Python Data Types and Variables Questions and Answers

Question 1

Which of the following data types is immutable in Python?

Accepted Answer

tuple

Answer

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))

Accepted Answer

15

Answer

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?

Accepted Answer

tuple

Answer

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?

Accepted Answer

2myVar

Answer

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)

Accepted Answer

10
20

Answer

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).

Python Practice Test

Python Practice Test

Python Data Types and Variables Questions and Answers