pyenv can be used to install Python outside of the Python binaries in the /usr/bin directory. In other words, Python installed with pyenv will not interfere or mess up Python that was installed from a Linux repo using apt-get, dnf or yum.

• Install Python on Linux using pyenv in your home directory (this article)
• Install Python on Linux using pyenv in a shared location

Your shell can then be configured to use pyenv Python so that all Python commands run in your shell use pyenv Python making this a nice solution for Python while not impacting the default installation of Python.

Let's start by listing the current version of Python that is installed.

~]# python --version
Python 2.7.5

Some Linux systems have both version 2 and version 3 of Python installed, so let's also check for Python 3.

~]# python3 --version
Python 3.6.8

Almost always, the Python binaries and symbolic links (more on this in a moment) are located in the /usr/bin directory.

]# ll /usr/bin/ | grep -i python
lrwxrwxrwx.   1 root root           7 Jul  9 02:24 python -> python2
lrwxrwxrwx.   1 root root           9 Jul  9 02:24 python2 -> python2.7
-rwxr-xr-x.   1 root root        7144 May 30 02:39 python2.7
-rwxr-xr-x.   1 root root        1835 May 30 02:39 python2.7-config
lrwxrwxrwx.   1 root root          16 Jul  9 02:24 python2-config -> python2.7-config
lrwxrwxrwx.   1 root root           9 Jul  9 02:24 python3 -> python3.6
-rwxr-xr-x.   2 root root       11336 May 30 07:42 python3.6
lrwxrwxrwx.   1 root root          17 Jul  9 02:24 python3.6-config -> python3.6m-config
-rwxr-xr-x.   2 root root       11336 May 30 07:42 python3.6m
-rwxr-xr-x.   1 root root         173 May 30 07:42 python3.6m-config
-rwxr-xr-x.   1 root root        3403 May 30 07:24 python3.6m-x86_64-config
lrwxrwxrwx.   1 root root          16 Jul  9 02:24 python3-config -> python3.6-config
lrwxrwxrwx.   1 root root          14 Jul  9 02:24 python-config -> python2-config

pyenv can be used to install Python outside of the Python binaries in the /usr/bin directory. In other words, Python installed with pyenv will not interfere or mess up Python that was installed from a Linux repo using apt-get, dnf or yum.

Let's install pyenv. This will create the hidden .pyenv directory in your home directory.

curl -fsSL https://pyenv.run | bash

There should now be a hidden .pyenv directory in your home directory.

~]$ ls -lisa $HOME
     1928  8 drwxr-xr-x. 20 john.doe users 4096 May  1 05:03 .
       64  4 drwxr-xr-x. 56 john.doe users 4096 May  1 05:15 ..
204475212  4 drwxr-xr-x. 14 john.doe users 4096 May  1 05:04 .pyenv

Let's determine your shell.

[john.doe@localhost ~]$ echo $SHELL
/usr/bash

If your shell is /bin/bash, issue the following commands to make the pyenv CLI available in your bash shell.

echo 'export PYENV_ROOT="/usr/local/share/.pyenv"' >> ~/.bashrc
echo '[[ -d $PYENV_ROOT/bin ]] && export PATH="$PYENV_ROOT/bin:$PATH"' >> ~/.bashrc
echo 'eval "$(pyenv init - bash)"' >> ~/.bashrc
echo 'export PYENV_ROOT="/usr/local/share/.pyenv"' >> ~/.bash_profile
echo '[[ -d $PYENV_ROOT/bin ]] && export PATH="$PYENV_ROOT/bin:$PATH"' >> ~/.bash_profile
echo 'eval "$(pyenv init - bash)"' >> ~/.bash_profile

Now both ~/.bashrc and ~/.bash_profile should contain the lines that were just appended.

~]# tail -3 ~/.bashrc
export PYENV_ROOT="/usr/local/share/.pyenv"
[[ -d $PYENV_ROOT/bin ]] && export PATH="$PYENV_ROOT/bin:$PATH"
eval "$(pyenv init - bash)"
~]# tail -3 ~/.bash_profile
export PYENV_ROOT="/usr/local/share/.pyenv"
[[ -d $PYENV_ROOT/bin ]] && export PATH="$PYENV_ROOT/bin:$PATH"
eval "$(pyenv init - bash)"

If your shell is /bin/sh, you may need to create the hidden .profile file in your home directory.

[john.doe@localhost ~]$ touch $HOME/.profile

And then issue the following commands to make the pyenv CLI available in your shell.

echo 'export PYENV_ROOT="/usr/local/share/.pyenv"' >> ~/.profile
echo '[[ -d $PYENV_ROOT/bin ]] && export PATH="$PYENV_ROOT/bin:$PATH"' >> ~/.profile
echo 'eval "$(pyenv init - bash)"' >> ~/.profile

And then reload your shell.

exec "$SHELL"

You should now be able to use the pyenv CLI.

~]$ pyenv --version
pyenv 2.5.5

Let's list the versions of Python that can be installed with pyenv. There will be much more output than listed here. This is just a short snippet of the output.

~]$ pyenv install --list
  3.12.0
  3.12-dev
  3.12.1
  3.12.2
  3.12.3
  3.12.4
  3.12.5
  3.12.6
  3.12.7
  3.12.8
  3.12.9
  3.12.10

At this point, the $HOME/.pyenv/versions directory should be empty as we have not yet installed Python using pyenv.

~]$ ls -lisa $HOME/.pyenv/versions/
total 4
166209121 0 drwxr-xr-x.  2 john.doe users    6 May  1 05:04 .
204475212 4 drwxr-xr-x. 14 john.doe users 4096 May  1 05:04 ..

Let's install a version of Python returned by the prior command. Notice that Python was installed in the /home/john.doe/.pyenv/versions directory in this example.

~]$ pyenv install 3.12.0
Downloading Python-3.12.0.tar.xz...
-> https://www.python.org/ftp/python/3.12.0/Python-3.12.0.tar.xz
Installing Python-3.12.0...
Installed Python-3.12.0 to /home/john.doe/.pyenv/versions/3.12.0

The pyenv global command show return "system" which means that "system" Python is being used (e.g. /usr/bin/python). 

~]# pyenv global
system

And the pyenv versions command will show that "system' Python is being used.

~]$ pyenv versions
* system
  3.12.0 (set by /home/john.doe/.pyenv/version)

Now let's use pyenv so that the python CLI will use the version of Python that we installed with pyenv.

• pyenv shell <version> - To make pyenv Python available for only your current shell session
• pyenv local <version> - To make pyenv Python available in your present working directory (and subdirectories)
• pyenv global <version> - To make pyenv Python available for your user account

pyenv global 3.12.0

Now the pyenv global command should return 3.12.0 (in this example) meaning that the python CLI is using pyenv Python version 3.12.0.

~]# pyenv global
3.12.0

And the pyenv versions command will show that Python version 3.12.0 is being used.

~]$ pyenv versions
  system
* 3.12.0 (set by /home/john.doe/.pyenv/version)

And the python --version command should return the version of Python that was installed by pyenv regardless of our present working directory. Nice!

~]$ python --version
Python 3.12.0

The pyenv local command should return the following because no local version has been set.

~]$ pyenv local
pyenv: no local version configured for this directory

Let's configure a local version of Python.

pyenv local 3.12.1

Now the pyenv versions command shows that version 3.12.1 of Python is being used, which means local takes precendence over global. This also creates the hidden .python-versions file in the present working directory.

~]$ pyenv versions
  system
  3.12.0
* 3.12.1 (set by /home/c065234/.python-version)

The hidden .python-versions file contains the local version of Python.

~]$ cat /home/c065234/.python-version
3.12.1

The pyenv local --unset command can be used to go back to using pyenv global.

pyenv local --unset

And the pyenv versions command now shows that the global version of pyenv is being used.

~]$ pyenv versions
  system
* 3.12.0 (set by /home/john.doe/.pyenv/version)
  3.12.1

Then let’s install the packages required by our Python scripts.

pip install --upgrade pip
pip install boto3
pip install Flask
pip install ipaddress
pip install paramiko
pip install requests
pip install ruamel.yaml
pip install pyopenssl
pip install datetime
pip install hvac
pip install jwt
pip install ldap3
pip install numpy
pip install oracledb
pip install ordered-set
pip install pandas

If you no longer want or need a certain version of Python that was installed in pyenv, you can uninstall it.

~]$ pyenv uninstall 3.12.1
pyenv: remove /home/john.doe/.pyenv/versions/3.12.1? (y/N) y
pyenv: 3.12.1 uninstalled