diff --git a/api/serializers.py b/api/serializers.py
index e0af85a..6f267e9 100644
--- a/api/serializers.py
+++ b/api/serializers.py
@@ -87,6 +87,7 @@ def create(self, validated_data):
         table_data = validated_data.pop("courses_data")
         collection = Collection.objects.create(**validated_data)
 
+        # First nested list will have first period of each day
         course_list = defaultdict(list)
         for order, periods in enumerate(table_data, 1):
             for day, period in enumerate(periods, 1):
diff --git a/api/views.py b/api/views.py
index 0eb1553..c23cce5 100644
--- a/api/views.py
+++ b/api/views.py
@@ -107,7 +107,8 @@ def get(self, request):
 
         schedules = Schedule.objects.filter(course__collection__user=request.user)
         max_order = schedules.aggregate(Max("order", default=1))["order__max"]
-        template = [[None] * max_order for i in range(5)]
+        # First nested list is the first period of each day, second nested list is second period of each day
+        template = [[""] * 5 for i in range(max_order)]
 
         for day in range(0, 5):
             schedules_on_day = schedules.filter(day_of_week=day + 1).order_by("order")