Update settings.py

src/aleph/settings.py

@@ -1,10 +1,27 @@
-from dataclasses import dataclass
+from dataclasses import dataclass, field
+from threading import Lock
 
 
-@dataclass(frozen=True, eq=True)
+@dataclass(frozen=True)
 class Settings:
-    use_executors: bool = True
+    """Immutable configuration settings."""
+    use_executors: bool = field(default=True)
 
+    _instance = None  # Private class-level variable for Singleton instance
+    _lock = Lock()  # Lock to ensure thread-safe initialization
 
-# Singleton
-settings = Settings()
+    @classmethod
+    def instance(cls):
+        """
+        Get the Singleton instance of the Settings class.
+        Ensures only one instance is created even in multithreaded environments.
+        """
+        if cls._instance is None:
+            with cls._lock:  # Double-checked locking
+                if cls._instance is None:
+                    cls._instance = cls()  # Initialize the Singleton instance
+        return cls._instance
+
+
+# Access the Singleton instance
+settings = Settings.instance()