def get_recommended_exercises(subtopic_id):
 if (not subtopic_id):
  return []
 tree = get_recommendation_tree(generate_recommendation_data())
 return tree[subtopic_id]

def get_recommended_exercises ( subtopic_id ) : if ( not subtopic_id ) : return [ ] tree = get_recommendation_tree ( generate_recommendation_data ( ) ) return tree [ subtopic_id ]
return a list of recommended exercises based on the given subtopic .