Python：WARNING: The version of Tcl/Tk (8.5.9) in use may be unstable.

When you first start up Python on a Mac, you might get the following warning:

>>> WARNING: The version of Tcl/Tk (8.5.9) in use may be unstable.Visit http://www.python.org/download/mac/tcltk/ for
current information.
If you get this warning, you'll need to update a graphics driver on your computer. Follow the link shown above and download and install the ActiveTcl driver that's recommend for the version of OS X that your Mac is running. This most likely will be 8.5.15.0,
which you can also download directly from http://www.activestate.com/activetcl/downloads (IMPORTANT:
you only need to do this step if you get the warning printed above when you start IDLE for the first time. If you don't get the warning, then everything is good to go.)