Lab 1: Introduction to Linux, Python Setup, and Your First Python Program

Objectives

Before we begin with the lab assignment, make sure you have the following setups done with the help of your TAs:

Open the Terminal
- Windows: Use Windows Subsystem for Linux (WSL) or Git Bash.
- macOS: Open Terminal from Applications > Utilities.
- Linux: Open Terminal from your applications menu.
Basic Commands
- pwd: Print Working Directory
```
pwd
```
  Outputs the current directory you are in.
- ls: List Directory Contents
```
ls
```
  Lists files and directories in the current directory.
- cd: Change Directory
```
cd /path/to/directory
```
  Changes the current directory to the specified path.
- mkdir: Make Directory
```
mkdir my_directory
```
  Creates a new directory named my_directory.
- touch: Create a New File
```
touch myfile.txt
```
  Creates a new empty file named myfile.txt.
- rm: Remove File
```
rm myfile.txt
```
  Deletes the file named myfile.txt.
- rmdir: Remove Directory
```
rmdir my_directory
```
  Deletes the directory named my_directory (must be empty).
- cp: Copy Files or Directories
```
cp source_file destination_file
```
  Copies source_file to destination_file.
- mv: Move or Rename Files or Directories
```
mv old_name new_name
```
  Renames old_name to new_name or moves old_name to new_name if it is a path.
Exercise:
- Create a directory named <YourEntryNumber>_COL100 (Eg 2024CS10001_COL100).
- Inside <YourEntryNumber>_COL100, create a file named hello.txt.
- List the contents of cs_intro to verify the file exists.
- Rename hello.txt to welcome.txt.
- Delete welcome.txt.

Check if Python is Installed
```
python3 --version
```
If Python is installed, it will display the version number.
Installing Python3
- Windows:
  - Download the Python installer from python.org.
  - Run the installer and follow the instructions (ensure "Add Python to PATH" is checked).
- macOS:
  - Python3 usually comes pre-installed. Use python3 --version to check.
  - If not, install it using Homebrew:
```
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
brew install python3
```
- Linux:
  - Install Python3 using your package manager:
    - Debian/Ubuntu:
```
sudo apt update
sudo apt install python3
```
    - Fedora:
```
sudo dnf install python3
```
Verify the Installation
```
python3 --version
```
You should see the version number of Python3.

Create a New Python File
- Navigate to your cs_intro directory:
```
cd cs_intro
```
- Create a new file named hello.py:
```
touch hello.py
```
Write Your First Python Program
- Open hello.py in a text editor (nano, vim, VS Code, etc.):
```
nano hello.py
```
- Add the following code to hello.py:
```
print("Hello, world!")
```
- Save and exit the editor (in nano, press CTRL + X, then Y, then Enter).
Run Your Python Program
```
python3 hello.py
```
You should see the output:
```
Hello, world!
```