Check whether python is installed

How to check if python is already installed?

To check the installed version of Python 2, run the following command: $ python2 —version To check the installed version of Python 3, run the following command: $ python3 —version Note that if you don’t specify the Python version, then it will use the default Python version. In this guide, we’ll check out various ways to check the version of Python installed in your system.

How to check if python is already installed?

When I tried whereis python it returns me following list:

python: /usr/bin/python3.8 /usr/lib/python3.9 /usr/lib/python2.7 /usr/lib/python3.8 /etc/python2.7 /etc/python3.8 /usr/local/lib/python3.8 /usr/include/python3.8

Does that mean Python is already installed in my machine ?

But when I try to yarn install in my project, it returns me following error:

gyp verb cli ] gyp info using node-gyp@3.8.0 gyp info using node@15.3.0 | linux | x64 gyp verb command rebuild [] gyp verb command clean [] gyp verb clean removing "build" directory gyp verb command configure [] gyp verb check python checking for Python executable "python2" in the PATH gyp verb `which` failed Error: not found: python2 

Your computer has python3.8 installed. To quickly check whether python2 is installed, run the command python2 —version , and your computer will most likely show command not found , because it is most likely not installed in your system.

Use the command sudo apt install python2 to install python2 .

Also, in the recent versions of Ubuntu, python2 has to be called with the command python2 , not just python .

Warning: Do not try to remove python3 , or change the default Python version to 2. python3.8 is preinstalled in your version of Ubuntu, and major components of Ubuntu depend on it. You can safely have both python2 and python3 installed.

You can check using python2 —version for python2 and python3 —version for python3. You can also use which python to verify which python will be used when called. Apparently it is installed in your machine, but yarn could not find it.

How to check all versions of python installed on osx and, Another command that could work is whereis python. In the event neither of these work, you can start the Python interpreter, and it will show you the version, or you could look in /usr/bin for the Python files (python, python3 etc). Share Improve this answer answered May 26, 2015 at 18:15 jm13fire 185 1 7 Add …

Different Ways to Check Python Version

Python is one of the most popular programming languages. In technical terms, it’s an interpreted, object-oriented , high-level programming language with dynamic semantics. It’s a relatively simple language. The unique syntax o f python focuses on readability. Python is open-source and available on all the major platforms.

As of now, Python 2 and Python 3 are the major releases that are still relevant. While Python 2 was marked obsolete, it’s still required for some codes to run. For the most part, however, having Python 3 is recommended. In this guide, we’ll check out various ways to check the version of Python installed in your system.

Prerequisites

To follow the steps demonstrated in this guide, you’ll need to have the following components ready to go.

• The latest version of Ubuntu. Learn more about installing Ubuntu on VirtualBox. This eliminates the concern of installing and configuring a new operating system from scratch.
• Familiarity with the command-line interface.

The Python version

Any Python version number has three components.

As mentioned before, Python 2 and Python 3 are the two major versions available. Python 2 is obsolete and the latest version released was Python 2.7.18. Here,

At the time of writing this article, the latest Python 3 is Python 3.10.2. Here,

Checking the Python version

Using the Python interpreter

Python comes the python command-line tool. It functions as both a Python shell and interpreter. We can ask this tool to print the version number of the Python installed.

To check the installed version of Python 2, run the following command:

To check the installed version of Python 3, run the following command:

Note that if you don’t specify the Python version, then it will use the defau lt python version. Note that you can have both Python 2 and Python 3 installed in the same system. Packages like python-is-python2 or python-is-python3 can influence the default Python version.

Using a Python script

We can create a simple Python script that will print the version info of the Python it’s running under.

The first example will incorporate the sys library. It comes with two ways of checking the version: the sys.version string and sys.version_info. In the following code, I’ve implemented both at the same time.

Another way is to use the platform library. Like sys, it also offers two ways of checking the Python version it’s running under the python_version() and python_version_tuple() functions. The following code demonstrates both of the functions at once.

import platform
print ( platform . python_version ( ) )
print ( platform . python_version_tuple ( ) )

Running Python codes without script

Instead of creating a dedicated script, we can run the Python codes directly from the command line. It compresses all the steps into a single command. For short and simple tasks like this, it’s a more optimal way.

Using the sys module

In the following command, we’re importing the sys module and printing the value of the sys.version .

Alternatively, you can print the value of sys.version_info.

Using the platform module

The following Python commands import the platform module and print the values of platform.python_version() and platform.python_version_tuple() functions.

Final Thoughts

In this short guide, we explored various ways to check the version of Python our code is running on. These techniques can come in handy when you’ve written a Python code that requires a specific version to function properly .

Interested in mastering Python? Check out our python su b-category. It’s rich in Python tutorials on various Python concepts, suitable for beginners to advanced developers.

What’s the default Python version in Ubuntu 20.04?, Ubuntu 20.04 has Python 3.8.2 as the default version. Python 2.7 has been moved to universe and is not included by default in any new installs. Official Release Notes about Python. Share. Improve this answer. edited May 11, 2021 at 3:12. D. S. 3 2. answered Apr 29, 2020 at 10:19.

How to install a specific Python version on Ubuntu

It is often the case that we install a program on our system, and it turns out that it’s the wrong version. This can lead to compatibility and performance issues since it may not communicate with third-party modules properly. Similar is the case with Python, and as vigilant programmers, we must figure out the correct version that we need. Therefore, in this guide, we will show you how to install a specific version of Python on your Ubuntu system.

Python on Ubuntu

Usually, Python comes preinstalled in many Linux distributions. In our case, we have Python3. Start a new Terminal session through the Activities menu or by pressing Ctrl + Alt +T on your keyboard. To be on the safe side of things, you can check whether your distro has Python installed or not by running the following command.

Or, if you are Running Python 3 like us, the command below ought to get the job done.

You can see in the image that the system is running Python 3.8.5. It is advised to upgrade your version of Python if you are running Python 3.3 or below. Stick around to find out more on which version you should get, as we will discuss that in the final segment of the article.

In the sections below, we will demonstrate how you can install any version of Python on your system, whether be it an updated one or an outdated one.

Installing a specific version of Python

The first step to installing Python is to install the necessary dependencies and packages that are required for its installation. However, to install these dependencies, you must have the multiverse repository enabled. You can enable it by running the command given below.

Once that is out of the way, we move on to installing the first dependency. Run the command below to proceed.

It should finish downloading and installing in a few moments. Once it is done, move on to the next one by running the command below.

$ sudo apt-get install libreadline-gplv2-dev libncursesw5-dev libssl-dev libsqlite3-dev tk-dev libgdbm-dev libc6-dev libbz2-dev

It is a long and complicated command so simply copy-paste it into your Terminal to avoid any typing errors.

Having done that, we move on to downloading Python and installing it. For the sake of showing you how to install a specific version, we will be downgrading our Python from 3.8.5 to Python 2.7.

First, we change the current directory to the Downloads folder where we wish to download the package. This can be done by running the command below.

The next step is to “wget” the package from the Python website.

Click here to access the location from where you can select any version of Python of your liking. All that needs to be amended in the wget command is the link.

Having successfully downloaded a specific version of Python, the final steps are simple and easy. First, we will extract the package through the command below.

You can replace the version number as Python- version .tgz according to your package.

The next steps include opening the python dir ectory, configuring the files, and installing it. Run the commands below in the given order to proceed.

The installation process, while it is straightforward and simple, should take a few minutes to complete. Once it’s done, you can check whether the installation was successful or not by simply running the commands we mentioned at the start.

As you can tell from the image, we have successfully downgraded from Python 3.8.5 to python 2.7.12 . You can do the same for any particular version of your choice.

Why you should install Python 3.5 or later

Now that we have covered the meat of the matter let’s talk about which Python version you should get and why.

Let’s start with the numbers. It makes sense that as time passes by, a utility or programming language progresses in terms of features and performance. Python 2.0 was released in 2000, Python 2.7 in 2010, whereas Python 3.0 was released in 2008, and Python 3.6 in 2016. The latest versions have more tools and libraries at your disposal, so it makes sense to use the later versions. However, it is understandable if you are trying to install an outdated version on purpose if some feature you need was removed later.

Python 2.0 is still used in many Linux systems as the default version. Some companies also use Python 2 for all their work. However, as the technology progresses, more and more companies are moving toward Python3. For instance, Instagram migrated its code-base from Python 2.7 to Python 3 in 2017. Similarly, Facebook is catching up and is upgrading its infrastructure to Python 3.4 and later.

Furthermore, Python 3 is easier to understand and learn for beginners. So if you happen to be just starting off with this programming language, it’s better to leave the veterans to the old ones and start your journey with a fresh and minted version of Python. In short, for those who haven’t already, consider upgrading your Python to version 3.5 or later.

Conclusion

In the modern era of computing, it is pertinent that we keep our systems updated, our software free of viruses, and our utilities upgraded to their latest versions. This way, we can make our daily tasks easier, simpler, and accurate. So being a programmer or developer helps to have the latest version of Python up and running on your system.

Python module all versions ubuntu Code Example, # View as version vise: for p in $(compgen -c python); do printf «%-16s» $p; $p —version; done python2.7 Python 2.7.6 python3.4m Python 3.4.3 # view as: $ …

How to list all python version ubuntu

check all python versions ubuntu

# View as version vise: for p in $(compgen -c python); do printf "%-16s" $p; $p --version; done python2.7 Python 2.7.6 python3.4m Python 3.4.3 # view **** compgen -c python python2.7 python3.4m

How to install a specific Python version on Ubuntu?, In some cases, you might need to install a very specific Python version on your Ubuntu server which might be different from the one that comes from the defau… In some cases, you might need to install a very specific Python version on your Ubuntu server which might be different from the one that comes …

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