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Aman Kumar
Aman Kumar

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Python Essentials Every Developer Should Know 🐍

Python is one of the most beginner-friendly yet powerful programming languages used in:

  • Web Development
  • Data Science
  • Automation
  • AI/ML
  • Cloud & DevOps
  • Testing Automation

In this article, we’ll cover some important Python concepts with practical examples.

1. Introduction to Python

Python is a high-level, interpreted programming language known for:

✅ Simple syntax
✅ Readability
✅ Huge ecosystem
✅ Cross-platform support

Example:

print("Hello, Python!")

Variables in Python:

name = "Aman"
age = 30
is_developer = True

print(name)
print(age)
print(is_developer)
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2. List vs Tuple

Both Lists and Tuples store collections of items.

| Feature            | List             | Tuple     |
|--------------------|------------------|-----------|
| Mutable            | ✅ Yes           | ❌ No |
| Syntax             | `[]`             |  `()`     |
| Performance        | Slightly slower  |  Faster   |
| Use Case           | Dynamic data     | Fixed data |
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List Example

fruits = ["apple", "banana", "mango"]

fruits.append("orange")

print(fruits)
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Output:

['apple', 'banana', 'mango', 'orange']

Tuple Example

colors = ("red", "green", "blue")

print(colors)

Trying to modify tuple:

colors[0] = "black"
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Output:

TypeError: 'tuple' object does not support item assignment

When to Use?

Use:

  • List → when data changes frequently
  • Tuple → when data should remain constant

3. Generators

Generators are memory-efficient functions that return values one at a time using yield.

Instead of storing all values in memory, generators produce values lazily.

Normal Function

def numbers():
    return [1, 2, 3]`

**Generator Function**
`def numbers():
    yield 1
    yield 2
    yield 3

gen = numbers()

print(next(gen))
print(next(gen))
print(next(gen))
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Output:

1
2
3

Why Use Generators?

✅ Memory efficient
✅ Useful for large datasets
✅ Faster iteration

Example:

def even_numbers(limit):
    for i in range(limit):
        if i % 2 == 0:
            yield i

for num in even_numbers(10):
    print(num)
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4. Decorators

Decorators allow you to modify the behavior of functions without changing their code.

Basic Decorator Example

def logger(func):
    def wrapper():
        print("Function execution started")
        func()
        print("Function execution ended")
    return wrapper

@logger
def say_hello():
    print("Hello!")

say_hello()
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Output:

Function execution started
Hello!
Function execution ended
Why Decorators?

Common uses:

  • Logging
  • Authentication
  • Authorization
  • Performance monitoring
  • Caching

5. functools.wraps(func)

When decorators wrap functions, original function metadata gets lost.

functools.wraps helps preserve:

  • Function name
  • Docstring
  • Metadata

Without wraps

def logger(func):
    def wrapper():
        print("Running function")
        func()
    return wrapper

@logger
def greet():
    """This is greet function"""
    print("Hello")

print(greet.__name__)
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Output:

wrapper

With wraps

from functools import wraps

def logger(func):

    @wraps(func)
    def wrapper():
        print("Running function")
        func()

    return wrapper

@logger
def greet():
    """This is greet function"""
    print("Hello")

print(greet.__name__)
print(greet.__doc__)
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Output:

greet
This is greet function

6. Class Method vs Static Method

Python provides three types of methods:

  • Instance Method
  • Class Method
  • Static Method

Instance Method

Works with object instances.

class Employee:

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

    def display(self):
        print(self.name)

emp = Employee("Aman")
emp.display()
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Class Method

Uses cls and works with class-level data.

class Employee:

    company = "Google"

    @classmethod
    def company_name(cls):
        print(cls.company)

Employee.company_name()
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Static Method

Does not access instance or class data.

class MathUtils:

    @staticmethod
    def add(a, b):
        return a + b

print(MathUtils.add(5, 3))
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7. Shallow Copy vs Deep Copy

Python provides two ways to copy objects.

Shallow Copy

Creates a new object but references nested objects.

import copy

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

shallow = copy.copy(original)

shallow[0][0] = 99

print(original)
print(shallow)
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Output:

[[99, 2], [3, 4]]
[[99, 2], [3, 4]]

Both changed because nested objects are shared.

Deep Copy

Creates completely independent copies.

import copy

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

deep = copy.deepcopy(original)

deep[0][0] = 99

print(original)
print(deep)
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Output:

[[1, 2], [3, 4]]
[[99, 2], [3, 4]]

Final Thoughts

These Python concepts are extremely important for:

  • Interviews
  • Backend Development
  • Automation
  • Production-level coding

Mastering them helps you write:
✅ Cleaner code
✅ Faster code
✅ More maintainable applications

If you found this useful, feel free to connect and share your favorite Python concept 🚀

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