WIP: Add graphs to workouts list view that show reps/weight, still need to refactor logic and dont display unless plot button(Need to add) is checked

utils.py

@@ -170,3 +170,16 @@ def first_and_last_visible_days_in_month(first_day_of_month, last_day_of_month):
     end_date = last_day_of_month + \
         timedelta(days=end[last_day_of_month.weekday()])
     return (start_date, end_date)
+
+
+def flatten(lst):
+    """
+    Flatten a list of lists.
+    """
+    result = []
+    for item in lst:
+        if isinstance(item, list):
+            result.extend(flatten(item))
+        else:
+            result.append(item)
+    return result