পাইথন ইন্টারভিউ প্রশ্ন 2026: উত্তর সহ শীর্ষ 30টি প্রশ্ন

# List — mutable
my_list = [1, 2, 3]
my_list.append(4)   # OK
my_list[0] = 10     # OK

# Tuple — immutable
my_tuple = (1, 2, 3)
# my_tuple[0] = 10  # TypeError!

# Tuples are faster and use less memory
# Use tuples for heterogeneous data (coordinates, RGB)
# Use lists for homogeneous, modifiable sequences

# Named tuples — readable tuples
from collections import namedtuple
Point = namedtuple('Point', ['x', 'y'])
p = Point(3, 4)
print(p.x, p.y)  # 3 4

import functools, time

def timer(func):
    @functools.wraps(func)
    def wrapper(*args, **kwargs):
        start = time.perf_counter()
        result = func(*args, **kwargs)
        elapsed = time.perf_counter() - start
        print(f"{func.__name__}: {elapsed*1000:.2f}ms")
        return result
    return wrapper

@timer
def slow_function():
    time.sleep(0.1)
    return 42

slow_function()  # "slow_function: 100.12ms" 

def func(*args, **kwargs):
    print(args)   # tuple of positional arguments
    print(kwargs) # dict of keyword arguments

func(1, 2, 3, name="Alice", age=30)
# (1, 2, 3)
# {'name': 'Alice', 'age': 30}

# Unpacking
def add(a, b, c): return a + b + c
numbers = [1, 2, 3]
print(add(*numbers))  # 6

settings = {"a": 1, "b": 2, "c": 3}
print(add(**settings))  # 6

# Generator — lazy evaluation, memory efficient
def fibonacci():
    a, b = 0, 1
    while True:
        yield a
        a, b = b, a + b

# vs list — loads everything into memory
fib = fibonacci()
print([next(fib) for _ in range(10)])

# Use generators when:
# 1. Processing large datasets (files, DB rows)
# 2. Infinite sequences
# 3. Building pipelines

class Circle:
    pi = 3.14159

    def __init__(self, radius):
        self.radius = radius

    # Regular method — receives instance (self)
    def area(self):
        return self.pi * self.radius ** 2

    # classmethod — receives class (cls), can access class variables
    @classmethod
    def from_diameter(cls, diameter):
        return cls(diameter / 2)  # factory method

    # staticmethod — receives nothing, utility function
    @staticmethod
    def is_valid_radius(radius):
        return radius > 0

c1 = Circle(5)
c2 = Circle.from_diameter(10)
print(Circle.is_valid_radius(-1))  # False

class A:
    def method(self): return "A"

class B(A):
    def method(self): return "B"

class C(A):
    def method(self): return "C"

class D(B, C):  # Multiple inheritance
    pass

d = D()
print(d.method())   # "B" — follows MRO
print(D.__mro__)    # (D, B, C, A, object)
# Python uses C3 linearization for MRO

import copy

original = [[1, 2, 3], [4, 5, 6]]

# Shallow copy — new list, but nested objects are shared
shallow = copy.copy(original)  # or list(original) or original[:]
shallow[0].append(99)
print(original[0])  # [1, 2, 3, 99] — MODIFIED! (shared reference)

# Deep copy — completely independent copy
deep = copy.deepcopy(original)
deep[0].append(88)
print(original[0])  # [1, 2, 3] — unchanged

import asyncio

# asyncio.gather — partial failures possible
async def example_gather():
    results = await asyncio.gather(
        task1(),
        task2(),
        return_exceptions=True  # don't cancel others on failure
    )
    # Results include exceptions if return_exceptions=True

# asyncio.TaskGroup (Python 3.11+) — all-or-nothing
async def example_task_group():
    async with asyncio.TaskGroup() as tg:
        t1 = tg.create_task(task1())
        t2 = tg.create_task(task2())
    # If any task raises, all are cancelled — structured concurrency

asyncio.run(example_task_group())