This can be done quickly by typing:

$ pip freeze >requirements.txt

at the command line.

To install packages using a requirements file just use pip:

$ pip install -r requirements.txt

To check if the packages in your requirements.txt file are up-to-date use:

$ pip list --outdated

and to update those packages:

$ pip install -U <packagename>

Start out by creating a new directory or cloning a repository (which creates a directory) and cd into it:

$ git clone https://gitlab.com/username/proj-name $ cd proj-name/

Initialize the virtual environment:

$ python3 -m venv venv $ source venv/bin/activate

Install whatever dependencies you need:

$ pip install package1 package2

Then develop and/or run your program: