diff --git a/python-package/vnstock/vnstock.py b/python-package/vnstock/vnstock.py
index 43bc0ac..ceb7b6c 100644
--- a/python-package/vnstock/vnstock.py
+++ b/python-package/vnstock/vnstock.py
@@ -1,84 +1,75 @@
 import pandas as pd
 import requests
 
-# Define the HEADERS dictionary
-HEADERS = {
-    'content-type': 'application/x-www-form-urlencoded',
-    'User-Agent': 'Mozilla'
-}
-
-def get_data(tickers, size=100):
-    """
-    Retrieves historical stock data from the VNDIRECT API for multiple tickers.
-
-    :param tickers: A list of stock symbols.
-    :param size: Length of historical data.
-    :return: A DataFrame containing historical stock data for all tickers.
-    """
-
-    # Check if tickers and size are valid
-    if not tickers:
-        raise ValueError("tickers is not set")
-
-    if size <= 0:
-        raise ValueError("size must be > 0")
-
-    # Define the base URL
-    base = "https://finfo-api.vndirect.com.vn/v4/stock_prices/"
-
-    # Initialize an empty DataFrame to store the results
-    df = pd.DataFrame()
-
-    for ticker in tickers:
-        # Check if the ticker is valid
-        if not isinstance(ticker, str) or len(ticker) != 3:
-            raise ValueError(f"Invalid ticker: {ticker}")
-
-        # Define the endpoint for each ticker
-        endpoint = f"code:{ticker}"
-        print(endpoint)
-
-        # Set query parameters, including the HEADERS
-        params = {
-            "sort": "date",
-            "size": size,
-            "page": 1,
-            "q": endpoint,
-        }
-
-        # Send the HTTP request with the HEADERS
-        res = requests.get(base, params=params, headers=HEADERS)
-
-        # Check if the HTTP request was successful
-        if res.status_code != 200:
-            print(f"Failed to retrieve data for ticker: {ticker}")
-            continue  # Skip to the next ticker on error
-
-        # Extract and process the data
-        data = res.json().get("data", [])
-
-        # Convert to a DataFrame
-        if data:
-            df_ticker = pd.DataFrame(data)
-            df_ticker["date"] = pd.to_datetime(df_ticker["date"])
-            df = pd.concat([df, df_ticker], ignore_index=True)
-        else:
-            print(f"No data available for ticker: {ticker}")
-
-    return df
-
-
-import pandas as pd
-
-def ohlcv(df):
-    """
-    Calculate OHLCV (Open, High, Low, Close, and Volume) from a DataFrame of stock prices.
-
-    :param df: A DataFrame containing stock price data with columns ['Date', 'Open', 'High', 'Low', 'Close', 'Adj Close', 'Volume'].
-    :return: A DataFrame containing OHLCV data with 'Date' as the index.
-    """
-    ohlcv_df = df[['date', 'open', 'high', 'low', 'close', 'adClose', 'nmVolume']]
-    ohlcv_df.columns = ['Date', 'Open', 'High', 'Low', 'Close', 'Adj Close', 'Volume']
-    ohlcv_df.index = pd.to_datetime(ohlcv_df['Date'])
-    return ohlcv_df
-
+class VNStockData:
+    HEADERS = {
+        'content-type': 'application/x-www-form-urlencoded',
+        'User-Agent': 'Mozilla'
+    }
+
+    def __init__(self):
+        self.base_url = "https://finfo-api.vndirect.com.vn/v4/stock_prices/"
+
+    def get_data(self, tickers, size=100):
+        """
+        Retrieves historical stock data from the VNDIRECT API for multiple tickers.
+
+        :param tickers: A list of stock symbols.
+        :param size: Length of historical data.
+        :return: A DataFrame containing historical stock data for all tickers.
+        """
+
+        # Check if tickers and size are valid
+        if not tickers:
+            raise ValueError("tickers is not set")
+
+        if size <= 0:
+            raise ValueError("size must be > 0")
+
+        # Initialize an empty DataFrame to store the results
+        df = pd.DataFrame()
+
+        for ticker in tickers:
+            # Check if the ticker is valid
+            if not isinstance(ticker, str) or len(ticker) != 3:
+                raise ValueError(f"Invalid ticker: {ticker}")
+
+            # Define the endpoint for each ticker
+            endpoint = f"code:{ticker}"
+            print(endpoint)
+
+            # Set query parameters, including the HEADERS
+            params = {
+                "sort": "date",
+                "size": size,
+                "page": 1,
+                "q": endpoint,
+            }
+
+            # Send the HTTP request with the HEADERS
+            res = requests.get(self.base_url, params=params, headers=self.HEADERS)
+
+            # Check if the HTTP request was successful
+            if res.status_code != 200:
+                print(f"Failed to retrieve data for ticker: {ticker}")
+                continue  # Skip to the next ticker on error
+
+            # Extract and process the data
+            data = res.json().get("data", [])
+
+            # Convert to a DataFrame
+            if data:
+                df_ticker = pd.DataFrame(data)
+                df_ticker["date"] = pd.to_datetime(df_ticker["date"])
+                df = pd.concat([df, df_ticker], ignore_index=True)
+            else:
+                print(f"No data available for ticker: {ticker}")
+
+        return df
+
+    def ohlcv(self, tickers, size=100):
+        df = self.get_data(tickers=tickers, size=size)
+        ohlcv_df = df[['date', 'open', 'high', 'low', 'close', 'adClose', 'nmVolume']]
+        ohlcv_df.columns = ['Date', 'Open', 'High', 'Low', 'Close', 'Adj Close', 'Volume']
+        ohlcv_df.index = pd.to_datetime(ohlcv_df['Date'])
+        return ohlcv_df
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