🐍 Python Full Course – Notes

This repository contains organized notes covering all major Python programming topics.
Perfect for beginners and intermediate learners.

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📚 Table of Contents

Python Installation and Setup

To start coding in Python, you need to install Python on your computer.

🔹 Download the latest version of Python from the official website:
👉 https://www.python.org/downloads/

🔹 Installers are available for Windows, macOS, and Linux.

🔹 While installing on Windows, make sure to check the option "Add Python to PATH" during the setup process.

🔹 After installation, verify it by running the following command in the terminal or command prompt:

python --version

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Running Python on Linux

Most Linux distributions (like Ubuntu, Fedora, Debian) come with Python pre-installed.

🔹 To check if Python is already installed, open the terminal and run:

python3 --version

🔹 If Python is not installed, you can install it using the package manager:

• For Debian/Ubuntu based systems:

sudo apt update
sudo apt install python3

• For Fedora:

sudo dnf install python3

🔹 After installation, verify by running:

python3 --version

✅ Now you can run Python programs using:

python3 filename.py

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Your First Python Program

Let's write and run your very first Python programs! 🎉

In Python, the print() function is used to display output on the screen.

Here are some basic examples:

print(200)            # Prints the number 200
print("Hello World")  # Prints the text Hello World
print(10 * 5)         # Prints the result of 10 multiplied by 5 (i.e., 50)
print(10 % 3)         # Prints the remainder when 10 is divided by 3 (i.e., 1)

How to run:

1. Open your code editor or terminal.
2. Save the code in a file named first.py.
3. Run the program:

• For Windows:

python first.py

• For Linux/macOS:

python3 first.py

---

Comments in Python

• Single-line comment example:

# Printing a number
print(200)

#  Printing a text message
print("Hello World")

# Printing the sum of two numbers
print(10 + 5)

# Printing the product of two numbers
print(10 * 3)

• Multi-line comment example:

'''
This is a multi-line comment.
You can use triple single quotes ('''or''') or triple double quotes (""" or """)
to write comments that span multiple lines.
'''

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Variables

🔹 How to create a variable in Python:

name = "Asif"
age = 22
price = 499.99
is_active = True

🔹 Roles of Variables:

• Store information (like numbers, text, etc.)
• Make code readable and organized
• Allow reuse of values without repeating
• Help in doing calculations and data processing easily

✅ In Python, you don't need to declare the type of a variable — Python automatically figures it out based on the assigned value.

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Data Types

Data types represent the kind of data a variable holds. Each value in Python has a specific type.

🔹 Common Data Types in Python:

• int — Integer numbers (e.g., 10, -5, 200)
• float — Decimal numbers (e.g., 10.5, 3.14)
• str — Strings/Text (e.g., "Hello", "Python")
• bool — Boolean (True or False)
• list — Ordered collection (e.g., [1, 2, 3])
• tuple — Immutable ordered collection (e.g., (1, 2, 3))
• dict — Key-Value pairs (e.g., {"name": "Asif", "age": 22})
• set — Unordered unique elements (e.g., {1, 2, 3})

🔹 Examples:

# Integer
x = 10

# Float
y = 20.5

# String
name = "Asif"

# Boolean
is_active = True

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

# Dictionary
student = {"name": "Asif", "age": 22}

✅ Python automatically sets the type when you assign a value.

How to Check the Type of a Variable

In Python, you can use the type() function to check what type of data a variable holds.

🔹 Example:

x = 10
print(type(x))   # Output: <class 'int'>

y = "Hello"
print(type(y))   # Output: <class 'str'>

✅ type() function helps you understand what kind of value a variable is storing.

---

Arithmetic Operations

In Python, arithmetic operations are used to perform basic mathematical calculations like addition, subtraction, multiplication, and division.

Operator	Description	Example	Output
+	Addition	5 + 3	8
-	Subtraction	5 - 3	2
*	Multiplication	5 * 3	15
/	Division	5 / 2	2.5
//	Floor Division	5 // 2	2
%	Modulus (Remainder)	5 % 2	1
**	Exponent (Power)	2 ** 3	8

Examples:

a = 10
b = 3

print(a + b)   # 13
print(a - b)   # 7
print(a * b)   # 30
print(a / b)   # 3.333...
print(a // b)  # 3
print(a % b)   # 1
print(a ** b)  # 1000

---

String Operations

In Python, strings are sequences of characters. You can perform many operations on strings like joining, slicing, repeating, and finding length.

Operation	Example	Output
Concatenation	"Hello " + "World"	Hello World
Repetition	"Hi " * 3	Hi Hi Hi
Length	len("Python")	6
Slicing	"Python"[0:3]	Pyt
Lowercase	"HELLO".lower()	hello
Uppercase	"hello".upper()	HELLO
Replace	"hello world".replace("world", "Python")	hello Python
Find	"hello".find("e")	1

Examples:

str1 = "Hello"
str2 = "World"

# Concatenation
print(str1 + " " + str2)    # Hello World

# Repetition
print(str1 * 3)             # HelloHelloHello

# Length
print(len(str2))            # 5

# Slicing
print(str1[0:3])            # Hel

# Lowercase and Uppercase
print(str2.lower())         # world
print(str1.upper())         # HELLO

# Replace
sentence = "I love Java"
print(sentence.replace("Java", "Python"))  # I love Python

# Find
print(str1.find('e'))       # 1

---

Lists

In Python, a list is a collection which is ordered and changeable (mutable). Lists allow duplicate elements.

1. Lists are defined using square brackets [].
2. Elements can be of different data types.
3. Lists are mutable (we can change, add, or remove items).
4. Lists allow duplicate values.
5. Common operations include indexing, slicing, adding, removing, and looping.

Operation	Example	Output
Create List	my_list = [1, 2, 3]	[1, 2, 3]
Indexing	my_list[0]	1
Slicing	my_list[0:2]	[1, 2]
Append	my_list.append(4)	[1, 2, 3, 4]
Insert	my_list.insert(1, 5)	[1, 5, 2, 3, 4]
Remove	my_list.remove(2)	[1, 5, 3, 4]
Pop	my_list.pop()	Removes last element 4
Length	len(my_list)	3 (after pop)

Examples:

# Creating a list
fruits = ["apple", "banana", "cherry"]

# Accessing elements
print(fruits[0])  # apple

# Slicing
print(fruits[0:2])  # ['apple', 'banana']

# Adding elements
fruits.append("orange")
print(fruits)  # ['apple', 'banana', 'cherry', 'orange']

# Inserting elements
fruits.insert(1, "mango")
print(fruits)  # ['apple', 'mango', 'banana', 'cherry', 'orange']

# Removing elements
fruits.remove("banana")
print(fruits)  # ['apple', 'mango', 'cherry', 'orange']

# Popping the last element
last_fruit = fruits.pop()
print(last_fruit)  # orange
print(fruits)      # ['apple', 'mango', 'cherry']

# Length of list
print(len(fruits))  # 3

✅ Lists are super flexible for storing multiple values in a single variable.

---

Tuples

In Python, a tuple is a collection which is ordered and immutable (cannot be changed after creation). Tuples allow duplicate elements.

1. Tuples are defined using parentheses ().
2. Elements can be of different data types.
3. Tuples are immutable (no add, remove, or change after creation).
4. Tuples allow duplicate values.
5. Useful when you want data to stay constant.

Operation	Example	Output
Create Tuple	my_tuple = (1, 2, 3)	(1, 2, 3)
Single Item Tuple	single = (5,)	(5,)
Indexing	my_tuple[1]	2
Slicing	my_tuple[0:2]	(1, 2)
Length	len(my_tuple)	3
Count Elements	my_tuple.count(2)	1
Find Index	my_tuple.index(3)	2

Examples:

# Creating a tuple
numbers = (1, 2, 3, 4)

# Accessing elements
print(numbers[0])  # 1

# Slicing
print(numbers[1:3])  # (2, 3)

# Length of tuple
print(len(numbers))  # 4

# Count specific value
print(numbers.count(2))  # 1

# Find index of a value
print(numbers.index(3))  # 2

# Single item tuple (must include comma)
single_item = (5,)
print(single_item)  # (5,)

✅ Tuples are perfect when you want fixed, read-only data in Python.

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Dictionaries

In Python, a dictionary is a collection of key-value pairs. Dictionaries are unordered, mutable, and indexed.

1. Dictionaries store data in key-value pairs.
2. Keys must be unique and immutable (like strings, numbers).
3. Values can be of any data type.
4. Dictionaries are mutable (can add, change, or remove key-value pairs).
5. Useful for structured data storage (like JSON).

Operation	Example	Output
Create Dictionary	my_dict = {"name": "Asif", "age": 20}	{'name': 'Asif', 'age': 20}
Access Value	my_dict["name"]	'Asif'
Add Item	my_dict["city"] = "Karachi"	Adds 'city': 'Karachi'
Update Value	my_dict["age"] = 21	Updates 'age': 21
Remove Item	my_dict.pop("city")	Removes 'city'
Keys List	my_dict.keys()	dict_keys(['name', 'age'])
Values List	my_dict.values()	dict_values(['Asif', 21])
Items (Pairs)	my_dict.items()	dict_items([('name', 'Asif'), ('age', 21)])

Examples:

# Creating a dictionary
student = {
    "name": "Asif",
    "age": 20,
    "course": "Python"
}

# Accessing values
print(student["name"])  # Asif

# Adding new key-value pair
student["city"] = "Karachi"
print(student)

# Updating value
student["age"] = 21
print(student)

# Removing a key-value pair
student.pop("course")
print(student)

# Getting all keys
print(student.keys())

# Getting all values
print(student.values())

# Getting all key-value pairs
print(student.items())

✅ Dictionaries are perfect for representing structured, real-world data.

---

Sets

In Python, a set is an unordered, unindexed, and mutable collection of unique elements.

1. Sets automatically remove duplicate values.
2. Sets are mutable, but elements must be immutable.
3. Sets do not support indexing or slicing.
4. Sets are useful for membership tests, removing duplicates, and mathematical operations (union, intersection).

Operation	Example	Output
Create Set	my_set = {1, 2, 3}	{1, 2, 3}
Add Element	my_set.add(4)	Adds 4 to the set
Remove Element	my_set.remove(2)	Removes 2
Discard Element	my_set.discard(5)	No error even if 5 not present
Union of Sets	set1.union(set2)	Combine sets
Intersection of Sets	set1.intersection(set2)	Common elements
Difference of Sets	set1.difference(set2)	Elements only in set1

Examples:

# Creating a set
fruits = {"apple", "banana", "cherry"}

# Adding an element
fruits.add("orange")
print(fruits)

# Removing an element
fruits.remove("banana")
print(fruits)

# Using discard (no error if element doesn't exist)
fruits.discard("pineapple")

# Set union
set1 = {1, 2, 3}
set2 = {3, 4, 5}
print(set1.union(set2))  # {1, 2, 3, 4, 5}

# Set intersection
print(set1.intersection(set2))  # {3}

# Set difference
print(set1.difference(set2))  # {1, 2}

✅ Sets are great for working with unique items and set operations.

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User Input

In Python, input() function is used to take input from the user.
The input is always received as a string. You can typecast it into other data types like int, float, etc.

Operation	Example	Output/Behavior
Take String Input	name = input("Enter your name: ")	User types input (e.g., "Asif")
Take Integer Input	age = int(input("Enter your age: "))	Converts input to integer
Take Float Input	price = float(input("Enter the price: "))	Converts input to float
Display User Input	print(name)	Prints the user input

Examples:

# Taking a string input
name = input("Enter your name: ")
print(f"Hello, {name}!")

# Taking an integer input
age = int(input("Enter your age: "))
print(f"You are {age} years old.")

# Taking a float input
price = float(input("Enter the product price: "))
print(f"The price is {price} dollars.")

# Simple calculation with user input
num1 = int(input("Enter first number: "))
num2 = int(input("Enter second number: "))
print(f"The sum is {num1 + num2}")

✅ input() is the way to interact with users in a Python program!

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Conditional Statements (If-Else-Elif)

In Python, conditional statements allow you to make decisions based on certain conditions.
The main keywords are if, else, and elif.

Statement	Purpose
if	Executes a block of code if the condition is true
elif	(Else If) Checks another condition if previous is false
else	Executes a block of code if all conditions are false

Syntax:

if condition:
    # code block
elif another_condition:
    # another code block
else:
    # code block if all conditions fail

# Basic if-else
age = int(input("Enter your age: "))
if age >= 18:
    print("You are eligible to vote.")
else:
    print("You are not eligible to vote.")

# Using elif
marks = int(input("Enter your marks: "))
if marks >= 90:
    print("Grade: A")
elif marks >= 75:
    print("Grade: B")
elif marks >= 60:
    print("Grade: C")
else:
    print("Grade: Fail")

# Multiple conditions
temperature = int(input("Enter the temperature: "))
if temperature > 30:
    print("It's hot outside!")
elif temperature > 20:
    print("The weather is pleasant.")
else:
    print("It's cold outside!")

✅ Conditional statements control the flow of your Python program based on conditions.

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Logical Operators (AND, OR)

Logical operators are used to combine multiple conditions.
Python mainly has three logical operators: and, or, and not.

Operator	Description	Example
and	Returns True if both conditions are true	(5 > 2) and (3 < 7) → True
or	Returns True if at least one condition is true	(5 > 8) or (3 < 7) → True

Examples:

# Using AND operator
age = int(input("Enter your age: "))
if age >= 18 and age <= 60:
    print("You are eligible to work.")
else:
    print("You are not eligible to work.")

# Using OR operator
day = input("Enter the day: ")
if day == "Saturday" or day == "Sunday":
    print("It's a weekend!")
else:
    print("It's a weekday.")

# Combining multiple conditions
score = int(input("Enter your score: "))
if score > 80 and score < 100:
    print("Excellent!")
elif score > 50 or score == 50:
    print("Good!")
else:
    print("Needs Improvement.")

✅ Logical operators make your conditional checks more powerful in Python!

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For Loops

In Python, a for loop is used to iterate over sequences like lists, tuples, strings, etc.

Use Case	Description
Loop over a list	Access each item in a list
Loop over a string	Access each character
Use with range()	Generate numbers in a sequence

Syntax:

for item in sequence:
    # code block

# Looping through a list
fruits = ["apple", "banana", "cherry"]
for fruit in fruits:
    print(fruit)

# Looping through a string
for letter in "Python":
    print(letter)

# Using range()
for i in range(5):
    print(i)   # Prints 0 to 4

# Using range with start and end
for i in range(2, 7):
    print(i)   # Prints 2, 3, 4, 5, 6

✅ for loops are perfect for repeating tasks automatically in Python!

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While Loops

A while loop in Python is used to execute a block of code repeatedly as long as a given condition is True.

Element	Description
while loop	Repeats code while the condition is true
break	Exits the loop early
continue	Skips to the next iteration

Syntax:

while condition:
    # code block

# Basic while loop
count = 1
while count <= 5:
    print("Count is:", count)
    count += 1

# Infinite loop with break
while True:
    num = int(input("Enter a number (0 to exit): "))
    if num == 0:
        break
    print("You entered:", num)

# Using continue
i = 0
while i < 10:
    i += 1
    if i % 2 == 0:
        continue  # Skip even numbers
    print(i)

✅ while loops are ideal when you don't know how many times you need to run the loop.

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Break and Continue Statements

In Python loops, break and continue are used to control the flow of the loop.

Statement	Description
break	Immediately exits the loop
continue	Skips the current iteration and moves to the next

---

break Example:

# Exit the loop when number is 3
for i in range(1, 6):
    if i == 3:
        break
    print(i)

# Output: 1, 2

Continue Example:

# Skip printing number 3
for i in range(1, 6):
    if i == 3:
        continue
    print(i)

# Output: 1, 2, 4, 5

✅ Use break to stop early, and continue to skip logic inside a loop.

---

Functions

Functions in Python are blocks of reusable code used to perform a specific task.

Concept	Description
def	Keyword to define a function
parameters	Input values to the function
return	Sends back a result from the function
default values	Assign default values to parameters

---

Basic Function Example:

def greet():
    print("Hello, Python!")

greet()

Function with Parameters:

def greet_user(name):
    print(f"Hello, {name}!")

greet_user("Asif")

Function with Return Value:

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

result = add(5, 3)
print(result)  # Output: 8

Function with Default Parameter:

def greet(name="Guest"):
    print(f"Hello, {name}!")

greet()          # Output: Hello, Guest!
greet("Asif")    # Output: Hello, Asif!

✅ Functions help in writing modular, reusable, and clean code.

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Using Python Code as a Module

In Python, any .py file can act as a module and can be imported into other Python scripts to reuse code.

Concept	Description
module	A Python file containing functions/classes
import	Keyword to load a module
from-import	Import specific parts of a module

---

Example:

math_utils.py

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

def subtract(a, b):
    return a - b

main.py

import math_utils

print(math_utils.add(10, 5))        # Output: 15
print(math_utils.subtract(10, 5))   # Output: 5

Using from ... import ...

from math_utils import add

print(add(3, 2))  # Output: 5

✅ Organizing your code into modules helps in reusability and clean architecture.

---

Object-Oriented Programming (OOP) in Python

OOP is a programming paradigm based on objects and classes that helps in organizing code and reusability.

Concept	Description
class	Blueprint for creating objects
object	Instance of a class
init	Constructor method, runs when object is created
self	Refers to the current instance of the class
method	Function defined inside a class

---

Basic OOP Example:

class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age

    def greet(self):
        print(f"Hello, my name is {self.name} and I am {self.age} years old.")

Creating object

p1 = Person("Asif", 23)
p1.greet()

Output

Hello, my name is Asif and I am 23 years old.

✅ OOP makes your code modular, scalable, and easier to maintain.

---

File Reading and Writing

In Python, you can use the built-in open() function to read from and write to files.

Mode	Description
'r'	Read (default mode)
'w'	Write (overwrite)
'a'	Append
'x'	Create new file
'rb'	Read binary
'wb'	Write binary

---

Writing to a File

with open("example.txt", "w") as file:
    file.write("Hello, this is a test file.")

Reading from a File

with open("example.txt", "r") as file:
    content = file.read()
    print(content)

Appending to a File

with open("example.txt", "a") as file:
    file.write("\nThis line is added later.")

✅ Always use with open(...) — it automatically closes the file after use.

---

Exception Handling

Exception handling in Python allows you to deal with errors gracefully without crashing the program.

Keyword	Description
try	Code block to test for errors
except	Code block to handle the error
else	Executes if no exception occurs
finally	Always executes (error or not)

---

Basic Example

try:
    num = int(input("Enter a number: "))
    print(10 / num)
except ZeroDivisionError:
    print("You can't divide by zero!")
except ValueError:
    print("Invalid input! Please enter a number.")
else:
    print("Division successful!")
finally:
    print("Execution completed.")

✅ Exception handling helps you build robust and user-friendly applications.

---

Random and Datetime Modules

Python provides built-in modules like random and datetime to work with randomness and date/time.

---

✅ random Module

Used to generate random numbers or make random selections.

import random

print(random.randint(1, 10))         # Random integer between 1 and 10
print(random.choice(["red", "blue", "green"]))  # Random choice from list

✅ datetime Module

Used to work with dates and times.

import datetime

now = datetime.datetime.now()
print("Current Date & Time:", now)

today = datetime.date.today()
print("Today's Date:", today)

# Formatting date
formatted = now.strftime("%d-%m-%Y %H:%M:%S")
print("Formatted Date & Time:", formatted)

✅ These modules are useful for games, logging, scheduling, and time-based logic.

---

Dice Game Project

This mini project simulates a dice roll using Python’s random module.

🎲 Code Example

import random

print("🎲 Dice Game 🎲")
input("Press Enter to roll the dice...")

dice = random.randint(1, 6)
print(f"You rolled a {dice}!")

🔁 Optional: Play Multiple Times

import random

while True:
    input("Press Enter to roll the dice (or Ctrl+C to exit)...")
    print(f"You rolled: {random.randint(1, 6)}\n")

✅ This is a fun way to practice the random module and while loop!

---

What is PyPI and PIP?

📦 PyPI (Python Package Index)

PyPI is the official third-party software repository for Python.
It contains thousands of packages and libraries that you can use in your Python projects.

🔗 Visit: https://pypi.org

---

📥 PIP (Python Installer Package)

PIP is the tool used to install packages from PyPI.

---

✅ Basic PIP Commands

Command	Description
pip install package-name	Install a package
pip uninstall package-name	Uninstall a package
pip list	List all installed packages
pip show package-name	Show info about a package
pip freeze > requirements.txt	Save installed packages to a file
pip install -r requirements.txt	Install from a requirements.txt

---

🔧 Example

pip install pandas

---

CSV Data Analysis using Pandas

The pandas library in Python is widely used for data analysis, especially with CSV files.

---

📥 Installing Pandas

pip install pandas

🧾 Reading CSV File

import pandas as pd

# Load data from a CSV file
data = pd.read_csv('data.csv')

# Display first 5 rows
print(data.head())

📊 Common Operations

print(data.shape)         # Rows and columns
print(data.columns)       # Column names
print(data.describe())    # Summary statistics
print(data['column_name'].value_counts())  # Count of unique values

🔍 Filtering Data

# Rows where age > 25
filtered = data[data['age'] > 25]
print(filtered)

✅ pandas makes it easy to manipulate, filter, and analyze CSV data in just a few lines of code.

---

Data Visualization using Matplotlib

matplotlib is a powerful Python library used to create static, animated, and interactive visualizations.

---

📥 Installing Matplotlib

pip install matplotlib

📈 Basic Line Plot

import matplotlib.pyplot as plt

x = [1, 2, 3, 4, 5]
y = [10, 20, 25, 30, 40]

plt.plot(x, y)
plt.title('Simple Line Chart')
plt.xlabel('X Axis')
plt.ylabel('Y Axis')
plt.show()

📊 Bar Chart

categories = ['A', 'B', 'C']
values = [10, 15, 7]

plt.bar(categories, values)
plt.title('Bar Chart')
plt.show()

🧁 Pie Chart

slices = [40, 35, 25]
labels = ['Python', 'JavaScript', 'C++']

plt.pie(slices, labels=labels, autopct='%1.1f%%')
plt.title('Pie Chart of Programming Languages')
plt.show()

✅ matplotlib is ideal for visualizing data with charts, graphs, and plots in Python.

---

Sending Emails using SMTP Library

Python provides the smtplib module to send emails using the Simple Mail Transfer Protocol (SMTP).

---

📥 Gmail SMTP Server Details

• SMTP Server: smtp.gmail.com
• Port: 587

---

✉️ Sending an Email with smtplib

import smtplib
from email.message import EmailMessage

# Create Email
msg = EmailMessage()
msg['Subject'] = 'Hello from Python'
msg['From'] = 'your_email@gmail.com'
msg['To'] = 'receiver_email@gmail.com'
msg.set_content('This is a test email sent from Python!')

# Send Email
with smtplib.SMTP('smtp.gmail.com', 587) as smtp:
    smtp.starttls()
    smtp.login('your_email@gmail.com', 'your_app_password')  # Use App Password (not real password)
    smtp.send_message(msg)

print("Email sent successfully!")

Important Notes

• Enable 2-Step Verification in your Gmail account.
• Create an App Password from your Google Account → Security → App Passwords.
• Never share or hardcode your credentials in public code.

✅ smtplib is useful for automating emails for notifications, alerts, or reports.

---

Weather App using API in Python

You can build a Weather App in Python using APIs like OpenWeatherMap to fetch real-time weather data.

🌐 Step 1: Get API Key

• Sign up at https://openweathermap.org
• Go to your profile → API Keys → Create and copy your API key

---

📥 Install Requests Module

pip install requests

Sample Code:

import requests

API_KEY = 'your_api_key_here'
city = 'Karachi'
url = f'https://api.openweathermap.org/data/2.5/weather?q={city}&appid={API_KEY}&units=metric'

response = requests.get(url)
data = response.json()

if data['cod'] == 200:
    temperature = data['main']['temp']
    description = data['weather'][0]['description']
    print(f"Temperature in {city}: {temperature}°C")
    print(f"Weather: {description}")
else:
    print("City not found or API error.")

🔐 Notes

• Always keep your API key secure (avoid pushing it to GitHub).
• You can use .env files or environment variables to hide your API key.

✅ This project helps you practice working with REST APIs, JSON data, and the requests library.

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Running Linux Commands using Python (Subprocess Module)

Python provides the subprocess module to run shell commands directly from your code.

📦 Import Subprocess

import subprocess

Run a Simple Linux Command

# Example: List all files in the current directory
result = subprocess.run(['ls', '-l'], capture_output=True, text=True)

print(result.stdout)

Check Command Success

if result.returncode == 0:
    print("Command executed successfully.")
else:
    print("Error occurred while executing the command.")

🔐 Security Tip Avoid passing untrusted user input directly to subprocess to prevent shell injection.

✅ This module is powerful when automating system tasks or writing scripts that interact with the operating system.

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🚀 About

These notes are designed to help learners move from basic Python concepts to more advanced programming skills. Ideal for building projects, automation, and real-world applications.

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