pipsalabim is really easy to use. Go to your python project and execute it as follows to start guessing your dependencies:

$ cd your-python-project/
$ pipsalabim report --help

usage: pipsalabim report [-h] [-r]

optional arguments:
  -h, --help          show this help message and exit
  -r, --requirements  Format output for requirements.txt file.

You need to run “pipsalabim update” before being able to generate a report.