diff --git a/example/trade_derivatives_en.ipynb b/example/trade_derivatives_en.ipynb
index 8395044..db5438a 100644
--- a/example/trade_derivatives_en.ipynb
+++ b/example/trade_derivatives_en.ipynb
@@ -136,11 +136,11 @@
    },
    "outputs": [],
    "source": [
-    "import okx.Market as MarketData\n",
+    "import okx.MarketData as MarketData\n",
     "\n",
     "flag = \"1\"  # live trading: 0, demo trading: 1\n",
     "\n",
-    "marketDataAPI = MarketData.Market(flag = flag)\n",
+    "marketDataAPI = MarketData.MarketAPI(flag = flag)\n",
     "\n",
     "result = marketDataAPI.get_tickers(instType = \"SWAP\")\n",
     "print(result)"