Bem simples:
Scapy é uma das principais bibliotecas interpretadas por linha de comando para função de sniffer de rede disponiveis para Phyton hoje.
Link externo:
https://scapy.readthedocs.io/en/latest/introduction.html#about-scapy
Scapy is a Python program that enables the user to send, sniff and dissect and forge network packets. This capability allows construction of tools that can probe, scan or attack networks.
In other words, Scapy is a powerful interactive packet manipulation program. It is able to forge or decode packets of a wide number of protocols, send them on the wire, capture them, match requests and replies, and much more. Scapy can easily handle most classical tasks like scanning, tracerouting, probing, unit tests, attacks or network discovery. It can replace hping, arpspoof, arp-sk, arping, p0f and even some parts of Nmap, tcpdump, and tshark.
Scapy uses the Python interpreter as a command board. That means that you can directly use the Python language (assign variables, use loops, define functions, etc.)
If you are new to Python and you really don’t understand a word because of that, or if you want to learn this language, take an hour to read the very good by Guido Van Rossum. After that, you’ll know Python :) (really!). For a more in-depth tutorial is a very good start too.