Python Course Notes

Introduction to Python

• Instructor: Mosh
• Overview of course content
  • Core concepts in Python
  • Build three projects

Project Overview

1. Build a beautiful website for an imaginary grocery store using Django
   • Homepage displays products
   • Admin area for managing stock
2. Machine Learning with Python
   • Predict music preferences based on user profiles
3. Automate boring tasks with Python
   • Example: process thousands of spreadsheets quickly

Getting Started with Python

Installation

• Download Python from python.org
• Check for the latest version (Python 3.7.2 or newer)
• Important: Add Python to PATH during installation (Windows)

Installing PyCharm

• Download from jetbrains.com/pycharm
• Use Community edition (free)
• Set up PyCharm for Python development

Writing Your First Python Program

1. Create a new project in PyCharm
2. Write your first Python program:

   print("Your Name")  
   

3. Run the program to see output

Drawing Shapes with Print Statements

• Learn to draw using print statements
• Example: Draw a dog using multiple print lines

Learning Python Concepts

Variables

• Variables store data temporarily in memory
• Can be integers, floats, strings, booleans

price = 10  
rating = 4.9  
name = "Mosh"  
is_published = True  

User Input

• Use input() function to get user input
• Example: greeting user by name

Control Flow in Python

If Statements

• If a condition is true, execute code

  if is_hot:  
      print("It's a hot day")  
  else:  
      print("It's a lovely day")  
  

Loops

• For Loops: Iterate over a collection (e.g., list or string)
• While Loops: Repeat as long as a condition remains true

Functions

• Define reusable blocks of code using functions
• Pass parameters and return values
• Example:

def greet_user():  
   print("Welcome")  

Classes and Objects

• Define new types using classes
• Use methods to define behaviors of an object

  class Dog:  
      def bark(self):  
          print("Woof!")  
  

Error Handling

• Use try and except blocks to handle exceptions
• Example: Capture value and division errors

try:  
   age = int(input("Enter your age: "))  
except ValueError:  
   print("Invalid age")  

Dictionaries

• Store key-value pairs for easy data access

customer = {'name': 'John', 'age': 30}  
print(customer['name'])  

Modules and Packages

• Organize related code into modules and packages
• Use import statements to bring in functionality

Built-in Modules

• Use standard libraries like math, random, etc.

Third-party Libraries from PyPI

• Install packages like openpyxl via pip to work with Excel files

Final Project: Automating Spreadsheet Data

• Open an Excel file
• Modify values and output results
• Include charts or graphs for visualization

Machine Learning Introduction

• Use ML for tasks like image recognition, predictions, etc.
• Discussed libraries: Numpy, Pandas, Scikit-learn
• Framework: Jupyter for code execution and data visualization

Conclusion

• Mosh encouraged students to share course insights and ask questions

---

• Next Steps: Work on a Django web application
• Key Concepts: Core Python, Errors, Classes, Functions, Data Manipulation, ML basics
• Personal Development: Explore your interest in AI and automation projects.

---