refactored model, fixed utf-8 export json

src/connector.py

@@ -29,6 +29,10 @@ class Connector(ABC):
     def create_new(self, values: dict) -> int:
         pass
 
+    @abstractmethod
+    def get_all_sorted_by(self, field: str, reverse: bool = False) -> list:
+        pass
+
 
 class JSONConnector(Connector):
     def __init__(self):
@@ -78,5 +82,5 @@ class JSONConnector(Connector):
         return next_id
 
     def _write_to_file(self, data):
-        with open(self.json_file, "w") as f:
-            json.dump(data, f, indent=4)
+        with open(self.json_file, "w", encoding="UTF-8") as f:
+            json.dump(data, f, indent=4, ensure_ascii=False)