Begin your Python journey - zamaniamin/python GitHub Wiki

There are several ways to get your own copy of Python 3, depending on the operating system you use.

Linux users most probably have Python already installed - this is the most likely scenario, as Python's infrastructure is intensively used by many Linux OS components.

For example, some distributors may couple their specific tools together with the system and many of these tools, like package managers, are often written in Python. Some parts of graphical environments available in the Linux world may use Python, too.

If you're a Linux user, open the terminal/console, and type:

python3

at the shell prompt, press Enter and wait. If you see something like this:

Python 3.11.5 (tags/v3.11.5:cce6ba9, Aug 24 2023, 14:38:34) on linux
Type "help", "copyright", "credits" or "license" for more information.
>>>

then you don't have to do anything else.

If Python 3 is absent, then refer to your Linux documentation in order to find out how to use your package manager to download and install a new package – the one you need is named python3 or its name begins with that.

All non-Linux users can download a copy at https://www.python.org/downloads/.

Because the browser tells the site you've entered the OS you use, the only step you have to take is to click the appropriate Python version you want.

In this case, select Python 3. The site always offers you the latest version of it.

If you're a Windows user, start the downloaded .exe file and follow all the steps.

Leave the default settings the installer suggests for now, with one exception - look at the checkbox named Add Python 3.x to PATH and check it.

This will make things easier.

If you're a macOS user, a version of Python 2 may already have been preinstalled on your computer, but since we will be working with Python 3, you will still need to download and install the relevant .pkg file from the Python site.

Now that you have Python 3 installed, it's time to check if it works and make the very first use of it.

This will be a very simple procedure, but it should be enough to convince you that the Python environment is complete and functional.

There are many ways of utilizing Python, especially if you're going to be a Python developer.

To start your work, you need the following tools:

an editor which will support you in writing the code (it should have some special features, not available in simple tools); this dedicated editor will give you more than the standard OS equipment;
a console in which you can launch your newly written code and stop it forcibly when it gets out of control;
a tool named a debugger, able to launch your code step-by-step, which will allow you to inspect it at each moment of execution.

Besides its many useful components, the Python 3 standard installation contains a very simple but extremely useful application named IDLE.

IDLE is an acronym: Integrated Development and Learning Environment.

Navigate through your OS menus, find IDLE somewhere under Python 3.x and launch it. This is what you should see:

Useful information regarding the error:

Traceback (most recent call last):
  File "C:/Users/admin/hello.py", line 1, in <module>
    prnt("Hissssss")
NameError: name 'prnt' is not defined. Did you mean: 'print'?

• the traceback (which is the path that the code traverses through different parts of the program - you can ignore it for now, as it is empty in such a simple code);
• the location of the error (the name of the file containing the error, line number and module name); note: the number may be misleading, as Python usually shows the place where it first notices the effects of the error, not necessarily the error itself;
• the content of the erroneous line; note: IDLE’s editor window doesn’t show line numbers, but it displays the current cursor location at the bottom-right corner; use it to locate the erroneous line in a long source code;
• the name of the error and a short explanation.

source: Python Institute