bring back ABC

Author: khvn26

flagsmith/offline_handlers.py

@@ -1,4 +1,5 @@
 import json
+from abc import ABC, abstractmethod
 from pathlib import Path
 from typing import Protocol
 
@@ -10,6 +11,12 @@ class OfflineHandler(Protocol):
     def get_environment(self) -> EnvironmentModel: ...
 
 
+class BaseOfflineHandler(ABC):
+    @abstractmethod
+    def get_environment(self) -> EnvironmentModel:
+        raise NotImplementedError()
+
+
 class LocalFileHandler:
     """
     Handler to load evaluation context from a local JSON file containing the environment document.