Lesson 0: Environments and Tools and Bears. Oh My!

A walkthrough of Python installation and developer tools.

The Beginning of the Beginning

Before we get started with writing code, we must first install Python.

We need something called the Python Interpreter.

The Python Interpreter is what defines Python. It takes your code, waves its magic wand at it, and transforms it into something your computer can understand. Believe it or not, your computer isn't as smart as you! It can't read or understand your words, and it sure can't feel emotions (yet). The Python Interpreter breaks down your code into a big soup of 1s and 0s (sort of) and passed it off to your computer to deal with the rest. Obviously, there are many steps being skipped over, but this is all you need to know for now.

Installation

So how can we get our hands on this mythical piece of software. Well, lucky for you, most modern operating systems come with some version of Python pre-installed. To check, open up a terminal window and enter the following.

python --version

terminal is the term that will be used to describe Command Prompt for Windows and Terminal for Mac and Linux.

Command Prompt can be found by typing cmd in the Windows Search Menu/Windows Button Menu

Terminal can be found by clicking Launchpad and typing terminal for Mac devices.

Linux users can press ctrl+alt+T.

If the command returns with Python followed by a version number greater than 3.8, then you can skip the next section

If not, we must install it ourselves.

Installing Python Manually

Head over to python.org and navigate your way to the downloads page. Find the appropriate download for your operating system. We will be using Python 3.8.9 for the majority of this course, but any newer version will work as well. Download that file and give it a run. If given the option, make sure to add Python to PATH and install pip.

When the installer has finished, type the version command back into terminal to ensure that Python has installed. You may need to restart your computer.

Integrated Development Environments (IDEs)

Now that you have Python installed, we need to figure out where to write our code.

We need an integrated development environment (IDE), which is a text editor for code that includes many features that will be of interest to us, like syntax highlighting. Python comes with its very own IDE, IDLE, right out of the box. While IDLE does come with all the features you may need to develop programs, it isn't ideal, especially as programs get increasingly more complex.

Material in this course is written for an IDE called Visual Studio Code, built by Microsoft. It is a free and open source code editor that can be found here. It is highly customizable, through extensions, and can be used for nearly every language out there, including Python. It is a monster of a program and not as friendly as IDLE, but making it your best friend will pay out in dividends.

Other popular IDEs for Python include PyCharm (created by JetBrains, often considered the best IDE maker), Sublime Text, and Atom.

You will be staring at your IDE for a very long time. Make sure to get comfortable with it, and to avoid jumping around between IDEs if you are new to programming.

Files and Directories

Once we have our tools ready, let's begin building our foundations.

Files, for the majority of this course, will be anything with the ending .py. Much like a text document may have the file ending in .txt, that tells you and your computer that that file is a text file, Python uses the file ending .py. All of your Python code will have to be inside a .py file. Every program will start with one file and end at one file (although other files can be called and used). Try to give your files names that make sense to the program. It isn't recommended to call your complex program newfile.py.

Directories are just folders. Directories can have files in them and they can be part of other directories. For consistency and convention, or something that is not required but is recommended, we will be putting files in their own independent directories.

This means that if we have a program like the one below, where we're printing a few things to the screen, the file main.py will be inside of a folder on it's own. The file name main.py tells us what it is, it's the main file. By having your non related scripts (another name for files in Python) inside their own directory, you can have a main.py file somewhere else without having a name conflict.

main.py

    print("We're off to see the wizard.")
    print("The wonderful Wizard of Oz.")

By making sure that files are given appropriate names and are isolated in appropriate directories, navigating your learning, projects, and work flow will be drastically improved. If you're working on a machine learning project, you don't want to be sifting through files for a game you made with PyGame.

Organization is the key to success. This will save you a lot of turmoil later on.

A strong foundation means you can build bigger and bigger things. A weak one will cost you a lot in the long run.