Suggestion: method to create requirements file only with the packages you use in project 

Instead with pip freeze, where you create a requirements file with all package dependencies or all packages in environment, you can use the following to only write out the packages you use in project: 

pipreqs --savepath=requirements.in && pip-compile 

See link below for more information: https://stackoverflow.com/questions/31684375/automatically-create-file-requirements-txt 