Python Course Lecture Notes

Introduction to Python

• Instructor: Mosh
• Python is a popular programming language used in various domains like automation, AI, web applications.
• Course includes core concepts and three projects.

Projects Overview

1. Grocery Store Website: Built using Django.
   • Homepage with product listings.
   • Admin area for stock management.
2. Machine Learning Application: Predicts music preferences based on user profiles.
3. Automation Scripts: Process spreadsheets quickly.

Getting Started with Python

• Installing Python:

  • Visit python.org
  • Download the latest version (e.g., Python 3.7.2).
  • Important: Check "Add Python to PATH" during installation.

• Installing Code Editor:

  • Recommended: PyCharm (IDEs for Python).
  • Download from jetbrains.com/pycharm.
  • Install the Community Edition (free).

First Python Program

• Create a new project in PyCharm.
• Write a simple program:

  print("I am Mosh Hamedani")
  

• Run the program using the "Run" menu or shortcuts.

Variables in Python

• Variables store data in memory.
• Example:

  price = 10  
  print(price)  # Outputs: 10
  

• Data Types: Integers, Floats, Strings, Booleans.

User Input

• To get user input:

  name = input("What is your name? ")
  print(f"Hi {name}")
  

Conditional Statements

• If Statements: Control flow based on conditions.

  if condition:
      # do something
  else:
      # do something else
  

Loops

• For Loops: Iterate over collections.

  for i in range(5):
      print(i)
  

• While Loops: Execute as long as a condition is true.

Functions

• Define reusable pieces of code.

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

Classes and Objects

• Classes: Blueprint for creating objects.

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

• Objects: Instances of classes.

Inheritance

• Allows one class to inherit properties and methods from another:

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

Modules and Packages

• Modules: Files containing Python code.
• Packages: Directories containing multiple modules.
• Example:

  import math  
  print(math.sqrt(16))  # Outputs: 4.0
  

Error Handling

• Use try/except to handle exceptions:

  try:
      age = int(input("Enter your age: "))
  except ValueError:
      print("Please enter a valid number.")
  

Comments

• Use # to add comments to code.
• Comments help explain why the code is written a certain way.

Conclusion

• Completed core concepts of Python.
• Encouragement to continue practicing and building projects.