Persist a Session Token to a file in JSON format.

        :type path: str
        :param path: The fully qualified path to the file where the
            the Session Token data should be written.  Any previous
            data in the file will be overwritten.  To help protect
            the credentials contained in the file, the permissions
            of the file will be set to readable/writable by owner only.

def save(self, file_path):
        """
        Persist a Session Token to a file in JSON format.

        :type path: str
        :param path: The fully qualified path to the file where the
            the Session Token data should be written.  Any previous
            data in the file will be overwritten.  To help protect
            the credentials contained in the file, the permissions
            of the file will be set to readable/writable by owner only.
        """
        fp = open(file_path, 'wb')
        json.dump(self.to_dict(), fp)
        fp.close()
        os.chmod(file_path, 0600)