# Create virtual env
python -m venv <my_virtual_env_folder_name>
or
virtualenv <my_virtual_env_folder_name>
# Set the new virtual env as source
source <my_virtual_env_folder_name>/bin/activate
# Install dependencies
pip install -r requirements.txt
# Install other dependencies
pip install <dependency_name>
# Create requirements.txt
pip freeze > requirements.txt