diff --git a/problems/trees/prune_tree.py b/problems/trees/prune_tree.py
index 5cb2a0c..43c4887 100644
--- a/problems/trees/prune_tree.py
+++ b/problems/trees/prune_tree.py
@@ -14,8 +14,12 @@ def prune_tree(tree, keys_to_discard):
     Returns: (Tree) the pruned tree.
     '''
     
-    pass
-
+    if tree.key in keys_to_discard:
+        return None
+    else: 
+        print(tree.key)
+        for subtree in tree.children: 
+            prune_tree(subtree) 
 
 #############################################################
 ###                                                       ###
@@ -122,4 +126,4 @@ def trees_prune_tree():
 def get_trees():
     trees = util.load_trees("sample_trees.json")
     original_trees = util.load_trees("sample_trees.json")
-    return trees, original_trees
\ No newline at end of file
+    return trees, original_trees