Improve structuring by defining TypedDicts and util classes here

src/wallman_classes.py

@@ -0,0 +1,25 @@
+from typing import TypedDict, List, Dict
+
+"""
+This is where library classes, like the config error
+And other utility things like TypedDicts for better
+linting and type checking go. I should also consider
+to move some other import here
+"""
+
+class ConfigError(Exception):
+    pass
+
+class ConfigGeneral(TypedDict):
+    enable_wallpaper_sets: bool
+    used_sets: List[str]
+    wallpapers_per_set: int
+    notify: bool
+    fallback_wallpaper: str
+    log_level: str
+    systray: bool
+    behavior: str
+
+class ConfigFile(TypedDict):
+    general: ConfigGeneral
+    changing_times: Dict[str, str]