how to run a python script on linux

2 min read 17-10-2024

Running Python Scripts on Linux: A Beginner's Guide

Python is a versatile programming language popular for its readability and vast libraries. Linux, with its command-line interface, provides a powerful platform for executing Python scripts. This guide will walk you through the steps of running Python scripts on Linux, catering to both beginners and those familiar with the command line.

Step 1: Writing your Python Script

Before running a script, you need to create one! Open your favorite text editor (like Nano, Vim, or Gedit) and write your Python code. For this example, let's use a simple script that prints "Hello, World!" to the console:

print("Hello, World!")

Save this script as "hello.py" in your desired directory.

Step 2: Checking Your Python Installation

To ensure you have Python installed on your Linux system, open a terminal window and type:

python --version

If you have Python installed, the terminal will display the version. If not, you can install Python using your Linux distribution's package manager. For example, on Ubuntu/Debian:

sudo apt-get update
sudo apt-get install python3

Step 3: Running Your Python Script

You can run your Python script in a few ways:

1. Using the python command:

Open your terminal and navigate to the directory containing your script using the cd command. Then, type:

python hello.py

This will execute your script and print "Hello, World!" to the terminal.

2. Using the python3 command:

If you have multiple Python versions installed, it's good practice to use the python3 command to ensure you're using the correct one:

python3 hello.py

3. Making your script executable:

You can make your script executable using the chmod command:

chmod +x hello.py

Then, you can run it directly by typing:

./hello.py

This method is convenient for frequently used scripts.

Step 4: Handling Dependencies

Your Python scripts might rely on external libraries (packages). To use these, you need to install them. For instance, if your script uses the requests library for making HTTP requests, you can install it using pip (Python package installer):

pip install requests

Additional Tips:

Shebang line: You can add a shebang line at the beginning of your script to specify the interpreter:
```
#!/usr/bin/env python3
print("Hello, World!")
```
This allows you to directly execute your script using its name:
```
./hello.py
```
Environment variables: You can define environment variables for your script's execution:
```
NAME="Alice"
python hello.py
```
Your script can then access these variables using the os.environ dictionary.
Virtual environments: For complex projects, consider using virtual environments to manage dependencies and avoid conflicts with other projects.

References:

This guide provides a comprehensive introduction to running Python scripts on Linux. Remember to explore the vast resources available online for more advanced topics like debugging, logging, and integrating your scripts into larger projects.