I copied the example profile code at the top and bottom of test_get and nearly all (7.155 / 7.210) of the time is in _socket.socket.connect, which takes .5 sec per call.
   14    7.155    0.511    7.155    0.511 {method 'connect' of _socket.socket' objects}
I am guessing that socket, and thence _socket, is imported in HTTPServer. I tested whether this diff in class TestServerThread is responsible
-         self.server = HTTPServer(('', 0), self.request_handler)
+         self.server = HTTPServer(('localhost', 0), self.request_handler)
but it is not.  Anyone else have other ideas?