paramiko/paramiko — pull request #459 by tkrapp (2014-12-16 22:38:20+00:00)
Title: Update agent.py to prevent ResourceWarning

When using Python 3 with warnings "enabled" you get a ResourceWarning each time the '_close'-method of AgentSSH is called.
Closing the socket stored in '_conn' explicitly before setting the attribute to None prevents this error.