how to enter into virtual environment code example

Example 1: create a venv

# Create the virtual environment.
python -m venv venv

# Activate the env.
venv\Scripts\activate.bat

Example 2: activate venv in python

(tutorial-env) $ pip freeze > requirements.txt
(tutorial-env) $ cat requirements.txt
novas==3.1.1.3
numpy==1.9.2
requests==2.7.0