Generate a virtual environment with, for example,

$ python -m venv syntax

where syntax is the name we're giving to the environment. After creating it, you can activate this environment with

$ source syntax/bin/activate

Install the dependencies with the command

$ pip install -r requirements.txt

To regenerate the syntax files (atf.tmLanguage.json and glo.tmLanguage.json), simply run

$ python generate_syntax_highlightining.py

or

$ ./generate_syntax_highlightining.py