How to create virtual env with python3

Python already ships with its builtin “virtualenv” called venv since version 3.3. You no longer need to install or download the virtualenv scripts for Python 3.3+.

https://docs.python.org/3/library/venv.html

Check that your installation provided the pyvenv command that should take care of creating the “virtualenv”. Arguments are similar to the classic virtualenv project.

$ pyvenv --help
usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear]
            [--upgrade] [--without-pip]
            ENV_DIR [ENV_DIR ...]

Creates virtual Python environments in one or more target directories.

positional arguments:
  ENV_DIR               A directory to create the environment in.

optional arguments:
  -h, --help            show this help message and exit
  --system-site-packages
                        Give the virtual environment access to the system
                        site-packages dir.
  --symlinks            Try to use symlinks rather than copies, when symlinks
                        are not the default for the platform.
  --copies              Try to use copies rather than symlinks, even when
                        symlinks are the default for the platform.
  --clear               Delete the contents of the environment directory if it
                        already exists, before environment creation.
  --upgrade             Upgrade the environment directory to use this version
                        of Python, assuming Python has been upgraded in-place.
  --without-pip         Skips installing or upgrading pip in the virtual
                        environment (pip is bootstrapped by default)

Once an environment has been created, you may wish to activate it, e.g. by
sourcing an activate script in its bin directory.

Install virtualenvwrapper on top of virtualenv to simplify things.
Follow the blog to install in easy steps: virtualenvwrapper

Steps to create it:

1. mkvirtualenv -p /usr/bin/python3
2. Install packages using – pip install package_name
3. workon – activates the virtualenv, deactivate – deactivates the viirtualenv

I install it using the command (for Python 3.x),

$ python3 -m venv env

To create virtual env

virtualenv -p python3 venv_name 

This will create new python executable in baseDirectory/bin/python3

How to activate newely created Venv:

cd baseDirectory/bin/  

source activate  

Deactivate new venv

deactivate 

UPDATE_1

This method has been depreciated as The use of venv is now recommended for creating virtual environments.
Please check this link for updated answer

To create a virtual environment in python3:

virtualenv -p /usr/bin/python3 virtualenvname

After creating the virtual environment, we need to activate it using the below command:

source virtualenvname/bin/activate

to deactivate use the below command:

deactivate

Since the launch of Python version 3.3, there has been no need to download the virtualenv package separately as it comes built-in in Python.

Refer to the documentation to gain complete insights on it.

Test the installation of virtualenv:

$ virtualenv --version 

Usage:

1.Creating a virtual environment:
$ virtualenv –system-site-packages -p python3 ./virtual_env_name

2.For enabling it, use the following command:
$ source ./virtual_env_name/bin/activate

3.For disabling the virtual environment and get back to working with the local environment:
$ deactivate

For listing down the packages in the virtual environment, use the
following command:
$ pip3 list

virtualenv is the tool of choice for Python 2, while venv handles the task in Python 3.

Yet you can create the virtual environment for Python 3 using any of them.

Using venv

python3 -m venv virtualenvname

Command Syntax:

/path/to/python3 -m venv /path/to/directory/virtual_env_name

Using virtualenv

virtualenv -p python3 virtualenvname

Command Syntax:

virtualenv -p /path/to/python3 /path/to/directory/virtual_env_name

Activate the virtual environment

On Linux, Unix or MacOS, using the terminal or bash shell:

source /path/to/venv/bin/activate

e.g. source virtualenvname/bin/activate

On Unix or MacOS, using the csh shell:

source /path/to/venv/bin/activate.csh

On Unix or MacOS, using the fish shell:

source /path/to/venv/bin/activate.fish

On Windows using the Command Prompt:

pathtovenvScriptsactivate.bat

On Windows using PowerShell:

pathtovenvScriptsActivate.ps1

Deactivating the virtual environment

On Linux, Unix or MacOS, using the terminal or bash shell:

deactivate

On Windows using the Command Prompt:

pathtovenvScriptsdeactivate.bat

On Windows using PowerShell:

deactivate

This answer is for those who may use a different OS.

If you are on windows.

1. manually download and install the version of python you want from the official site

2. after installation, search "python" to locate the folder, so you can identify the path

3. get the path of the .exe (for example: C:UsersPathProgramsPythonPython38python.exe)

4. Inside the folder of which you want to create the environment…start bash or VSCode terminal, or whatever command prompt, type [python .exe path] -m venv [env name] like this:

   C:/Users/Path/Programs/Python/Python38/python.exe -m venv myenv

5. (Note that you have to change forward slash to backward slash for the path on step 4)

6. Activate the environment like so:

   source myenv/Scripts/activate

CREATE VIRTUAL ENVIRONMENT:

For Python 3 version:

Command: python3 -m venv [environment_name]

Example: python3 -m venv my_virtual_environment

For Python 2 version:

Command: python -m [environment_name]

Example: python -m venv my_virtual_environment

ACTIVATE VIRTUAL ENVIRONMENT IN LINUX:

Go to the virtual environment directory then open terminal.

Command: source [environment_name]/bin/activate

Example: source my_virtual_environment/bin/activate

ACTIVATE VIRTUAL ENVIRONMENT IN WINDOWS:

Go to the virtual environment directory then open cmd.

Command: [environment_name]Scriptsactivate

Example: my_virtual_environmentScriptsactivate