secdev/scapy ? reverse-engineered prompt

Build me a Python tool that lets me create, send, sniff, and inspect network packets from an interactive command line, and also use the same code as a normal library in my own scripts.

I want it to be good for quick network testing, discovery, and packet debugging, with support for reading and writing pcap files, matching requests and replies, and easily building packets with sensible defaults. It should work well for common things like ping style checks, traceroute style probing, and basic packet crafting, but also let me go deeper when I need to manually tweak fields or send unusual packets.

Please make it cross platform if possible, with a clean interactive shell experience and clear examples in the docs so someone can try it quickly. If you need current details from the ecosystem or platform specific setup, look up the latest docs online before implementing anything.