Teach Yourself VISUALLY Python

CHAPTER 2

Writing and Running Your First Python Code

In this chapter, you start writing code in Python using the Visual Studio Code editor and the terminal window. You learn about Python’s main() function and create a simple function. You also learn how to run code either in Visual Studio Code or in a terminal window, add comments to your code, and import and use Python modules and objects.

Understanding the main() Function

Create and Save a New Script in Visual Studio Code

Write and Run Code in Visual Studio Code

Execute Python Commands in a Terminal Window

Run a Python Script in a Terminal Window

Understanding Comments in Python

Add Comments to Your Code

Grasp Importing Modules and Objects

Import Modules and Use Their Methods

Understanding the main() Function

You can create a Python script that simply uses commands and does not define any functions; you do this extensively later in this book. But many Python scripts include a function called main() that contains the main set of actions the script performs. In this section, you learn the purpose of the main() function and when and how to create one.

You also learn about the two ways to run code using the Python interpreter. How you run a script affects how Python sets the built-in __name__ parameter, which you can use to control whether the main() function runs.

What Is the main() Function?

As its name suggests, the main() ...