Saves the session variables to a file so that the same analysis can be continued later.

def do_fontsave(self, arg):
        """Saves the session variables to a file so that the same analysis can be continued later."""
        #We need to save the full paths to the staging directories for the tests that are loaded
        #so far; then when the session is restored, we can reparse the results.
        from os import path
        import json
        fullpath = path.expanduser(arg)
        data = {
            "fonts": self.curargs["fonts"],
            "ticks": self.curargs["ticks"]
        }
        with open(fullpath, 'w') as f:
            json.dump(data, f)
        msg.okay("Saved current font settings to {}".format(fullpath))