Python Exam Questions

Common Python exam questions across theory, programs, and short answers. Skim before any written paper or campus interview.

• What is Python and who created it? A high-level, interpreted, dynamically-typed language created by Guido van Rossum in 1991.
• Why is Python called interpreted? Source is converted to bytecode and executed line-by-line by the CPython virtual machine — no separate compilation step.
• List vs Tuple. List is mutable ([1,2,3]), tuple is immutable ((1,2,3)); tuples are faster and hashable.
• What is PEP 8? The official Python style guide (indentation = 4 spaces, snake_case names, etc.).
• What are mutable vs immutable types? Mutable: list, dict, set. Immutable: int, float, str, tuple, frozenset, bool.

• WAP to check prime number (loop till √n).
• WAP to reverse a string (s[::-1]).
• WAP to find Fibonacci series using recursion + memoization.
• WAP to count vowels in a string.
• WAP to sort a list without sort() (bubble or selection).

python Run in compiler
print(2 ** 3 ** 2)        # 512  (right-associative)
print([1,2,3] * 2)        # [1, 2, 3, 1, 2, 3]
print(bool([]), bool('0'))# False True
print('a' + str(1))       # 'a1'

• is vs == — is checks identity (same object), == checks value.
• *args vs **kwargs — positional and keyword variable-length arguments.
• Lambda — anonymous one-line function: lambda x: x*2.
• List comprehension — [x*x for x in range(5) if x%2==0].
• Decorator — function that wraps another function (@staticmethod, @classmethod).

• 4 OOP pillars in Python: Encapsulation, Inheritance, Polymorphism, Abstraction.
• __init__ is the constructor.
• self refers to the current instance.
• Multiple inheritance is allowed (uses MRO — Method Resolution Order via C3 linearization).

• Always import modules at the top, not inside functions.
• Use with open(...) for file handling (auto-closes).
• Memorize time complexity of dict/set lookups (O(1)) — common viva question.
• Quote PEP 8 in your essays — examiners love it.