diff --git a/ch9/ch9-07.md b/ch9/ch9-07.md
index 56a086a..63f5bbe 100644
--- a/ch9/ch9-07.md
+++ b/ch9/ch9-07.md
@@ -163,9 +163,6 @@ type Memo struct {
 
 // Get is concurrency-safe.
 func (memo *Memo) Get(key string) (value interface{}, err error) {
-    res, ok := memo.cache[key]
-    if !ok {
-	res.value, res.err = memo.f(key)
 	memo.cache[key] = res
 	memo.mu.Lock()
 	res, ok := memo.cache[key]