Scapy is a powerful interactive packet manipulation tool, packet generator, network scanner, network discovery tool, and packet sniffer. It provides classes to interactively create packets or sets of packets, manipulate them, send them over the wire, sniff other packets from the wire, match answers and replies, and more. Interaction is provided by the Python interpreter, so Python programming structures can be used (such as variables, loops, and functions). Report modules are possible and easy to make. It is intended to do about the same things as ttlscan, nmap, hping, queso, p0f, xprobe, arping, arp-sk, arpspoof, firewalk, irpas, tethereal, tcpdump, etc.
dnspython is a DNS toolkit for Python. It supports almost all of the record types. It can be used for queries, zone transfers, and dynamic updates. It supports TSIG authenticated messages and EDNS0. dnspython provides both high and low level access to DNS. The high level classes perform queries for data of a given name, type, and class, and return an answer set. The low level classes allow direct manipulation of DNS zones, messages, names, and records.
Xmpppy is a Python library grown from the jabberpy project. Though this library has borrowed some code from jabberpy, it is a separate project with its own architecture and slightly different API. It is primarily intended to be used with the RFC-compliant jabber servers (like ejabberd), but it should work with all popular servers (including GTalk).
pywrat (Python Wrappers for Remote Access Tools) is a set of wrappers that can be used for accessing remote hosts. They use ssh and scp for remote shell and file system access and can be used as a generalized access method with a single configuration file for all host, user, and key setups. The wrappers are intended to simplify remote access in shell scripts, but it is also possible to use the wrapper modules directly from Python programs.