fix: py3.8 complient

auto_trading/predictor/selector.py

@@ -10,4 +10,4 @@ class SelectorPredictor(Predictor):
     
     def predict(self, data: pd.DataFrame) -> dict:
         """It's just random"""
-        return {k:0 for k in data.to_dict().keys()} | self.to_return
+        return {**{k:0 for k in data.to_dict().keys()}, **self.to_return}