pwntools

 https://pwntools.readthedocs.io/en/stable/

pwntools is one of THE Python tools needed during a CTF. It is useful for both jeopardy and attack-defense CTFs. It provides common abstractions, like connecting to a local or remote program and simplifying I/O. Addtionally, it provides helpers for many exploitation techniques, such as ROP, shellcode, and leaking memory.