in chat-client/main.py [0:0]
def _get_expanded_subscription_set(subscribed_items, category_map):
initial_set = set(subscribed_items)
expanded_set = set(initial_set) # Start with explicit items
for category_tag, category_list in category_map.items():
if category_tag in initial_set:
# If the user subscribed to a category tag, add all items from that category
expanded_set.update(category_list)
return expanded_set