lots of typing fixes

app/terraform/list/__init__.py

@@ -1,4 +1,5 @@
 import json
+from typing import List
 
 from app import app
 from app.lists.mirror_mapping import mirror_mapping
@@ -9,7 +10,18 @@ from app.terraform.terraform import TerraformAutomation
 
 
 class ListAutomation(TerraformAutomation):
-    def tf_generate(self):
+    template: str
+    """
+    Terraform configuration template using Jinja 2.
+    """
+
+    template_parameters: List[str]
+    """
+    List of parameters to be read from the application configuration for use
+    in the templating of the Terraform configuration.
+    """
+
+    def tf_generate(self) -> None:
         self.tf_write(
             self.template,
             lists=MirrorList.query.filter(