Update city.py

Author: ipipdotnet

ipdb/city.py

@@ -13,6 +13,7 @@ class CityInfo:
     country_name = ""
     region_name = ""
     city_name = ""
+    district_name = ""
     owner_domain = ""
     isp_domain = ""
     latitude = ""
@@ -102,4 +103,4 @@ def fields(self):
         return self.db.support_fields()
 
     def build_time(self):
-        return self.db.build_utc_time()
+        return self.db.build_utc_time()