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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 _FormatReturnOrExitToken(self, token_data):
 """Formats a return or exit token as a dictionary of values. Args: token_data (bsm_token_data_exit|bsm_token_data_return32| bsm_token_data_return64):
 AUT_EXIT, AUT_RETURN32 or AUT_RETURN64 token data. Returns: dict[str, str]: token values. """

    error_string = bsmtoken.BSM_ERRORS.get(token_data.status, 'UNKNOWN')
    return {
        'error': error_string,
        'token_status': token_data.status,
        'call_status': token_data.return_value}