[Mod] type declaration

Author: noranhe

vnpy_postgresql/postgresql_database.py

@@ -179,7 +179,7 @@ def save_bar_data(self, bars: List[BarData]) -> bool:
         )
 
         if not overview:
-            overview: DbBarOverview = DbBarOverview()
+            overview = DbBarOverview()
             overview.symbol = symbol
             overview.exchange = exchange.value
             overview.interval = interval.value
@@ -375,7 +375,7 @@ def get_bar_overview(self) -> List[BarOverview]:
             self.init_bar_overview()
 
         s: ModelSelect = DbBarOverview.select()
-        overviews: list = []
+        overviews: List[BarOverview] = []
         for overview in s:
             overview.exchange = Exchange(overview.exchange)
             overview.interval = Interval(overview.interval)