diff --git a/iqfeed/iqfeed.py b/iqfeed/iqfeed.py
index 8b4ba96..1cf1726 100644
--- a/iqfeed/iqfeed.py
+++ b/iqfeed/iqfeed.py
@@ -69,12 +69,12 @@ def get_historical_data(symbol: str, interval: int,
         end_filter_time: datetime = datetime.strptime('160000', '%H%M%S').time()) -> pd.DataFrame:
     
     message = 'HIT,{symbol},{interval},{begin},{end},,{begin_filter},{end_filter},1\n'.format(
-        symbol=symbol,
-        interval=interval,
-        begin=start_date.strftime('%Y%m%d %H%M%S'),
-        end=end_date.strftime('%Y%m%d %H%M%S') if end_date else '',
-        begin_filter=start_filter_time.strftime('%H%M%S') if start_filter_time else '',
-        end_filter=end_filter_time.strftime('%H%M%S') if end_filter_time else ''
+        symbol = symbol,
+        interval = interval,
+        begin = start_date.strftime('%Y%m%d %H%M%S'),
+        end = end_date.strftime('%Y%m%d %H%M%S') if end_date else '',
+        begin_filter = start_filter_time.strftime('%H%M%S') if start_filter_time else '',
+        end_filter = end_filter_time.strftime('%H%M%S') if end_filter_time else ''
     )
 
     sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
@@ -89,7 +89,7 @@ def get_historical_data(symbol: str, interval: int,
     data = data.replace(',\n','\n')[:-1]
 
     data = StringIO(data)
-    return pd.read_csv(data, index_col=False, 
+    return pd.read_csv(data, index_col = False, 
         names=['Date', 'High', 'Low', 'Open', 'Close', 'Total Volume', 'Period Volume'])
 
 if __name__ == '__main__':