First python library that you need to install is Pillow. For more information about Pillow library, visit the documentation site https://pillow.readthedocs.io/en/5.1.x/. To install this library, use this command
pip3 install Pillow
Second library is xlsxwriter. This library will export the result of screenshoot to excel file. For more information about this library, visit the documentation site http://xlsxwriter.readthedocs.io/. To install this library, use this command
pip3 install xlsxwriter
Third library is selenium, for more information about this library, visit the documentation site http://selenium-python.readthedocs.io/index.html. To install this library, use this command
pip3 install selenium
Last, you need to install chromedriver. To instal chromedriver, you can follow tutorial on this site https://gist.github.com/ziadoz/3e8ab7e944d02fe872c3454d17af31a5
python3 CactiScreenshoot.py