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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 get_trade_fee(self, **params):
 """Get trade fee. https://github.com/binance-exchange/binance-official-api-docs/blob/master/wapi-api.md#trade-fee-user_data :param symbol: optional :type symbol: str :param recvWindow: the number of milliseconds the request is valid for :type recvWindow: int :returns: API response .. code-block:: python { "tradeFee": [ { "symbol": "ADABNB", "maker": 0.9000, "taker": 1.0000 }, { "symbol": "BNBBTC", "maker": 0.3000, "taker": 0.3000 } ], "success": true } :raises: BinanceWithdrawException """

        res = self._request_withdraw_api('get', 'tradeFee.html', True, data=params)
        if not res['success']:
            raise BinanceWithdrawException(res['msg'])
        return res