diff --git a/day7/day7.py b/day7/day7.py
index 22b9cc2..8394706 100644
--- a/day7/day7.py
+++ b/day7/day7.py
@@ -27,24 +27,24 @@ def process_rules(rules):
 
     return rules_dict
 
-def can_contain(rules, colour):
+def parents_of(rules, colour):
     parents = set()
     for parent, children in rules.items():
         if colour in children:
             parents.add(parent)
-            parents |= can_contain(rules, parent)
+            parents |= parents_of(rules, parent)
     return parents
 
-def colour_contains(rules, colour):
+def children_of(rules, colour):
     children = defaultdict(lambda: 0)
     for child_colour, child_num in rules[colour].items():
         children[child_colour] += child_num
-        for col, num in colour_contains(rules, child_colour).items():
+        for col, num in children_of(rules, child_colour).items():
             children[col] += child_num * num
     return children
 
 if __name__ == '__main__':
     bag_rules = [rule.strip() for rule in sys.stdin.readlines()]
     rules = process_rules(bag_rules)
-    print(len(can_contain(rules, 'shiny gold')))
-    print(sum(colour_contains(rules, 'shiny gold').values()))
+    print(len(parents_of(rules, 'shiny gold')))
+    print(sum(children_of(rules, 'shiny gold').values()))