code: def connect(self):
          
          if ('SSH_AUTH_SOCK' in os.environ) and (sys.platform != 'win32'):
              conn = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
              try:
                  retry_on_signal(lambda: conn.connect(os.environ['SSH_AUTH_SOCK']))
              except:
                  # probably a dangling env var: the ssh agent is gone
                  return
          elif sys.platform == 'win32':
              import win_pageant
              if win_pageant.can_talk_to_agent():
                  conn = win_pageant.PageantConnection()
              else:
                  return
          else:
              # no agent support
              return
          self._conn = conn
docs: Method automatically called by the run() method of the AgentProxyThread