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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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)