add deserialization of TimeSlot

lib/DataStore.py

@@ -7,13 +7,24 @@ class DataStore:
     def __init__(self, filename: Path, create=False):
         self._filename = filename
         if create:
+            # Store emtpty list
             self._time_slots = []
             self._write_update()
         else:
+            # Load dicts from file
             with open(self._filename, "r") as f:
                 self._time_slots = list(json.load(f))
 
+            # Convert dicts into TimeSlot objects
+            def deserialize(d: dict) -> TimeSlot:
+                ts = TimeSlot.__new__(TimeSlot)  # Create a new, empty instance
+                ts.__dict__.update(d)
+                return ts
+
+            self._time_slots = [deserialize(d) for d in self._time_slots]
+
     def _write_update(self):
+        """Saves the updates made to the DataStore object to disk."""
         with open(self._filename, "w+") as f:
             json.dump(self._time_slots, f, default=vars)