Fixed parentheses issue

model.py

@@ -198,7 +198,7 @@ class VAE(tf.keras.Model):
     """
       
     if z_sample == None:
-      z_sample = tf.expand_dims(tf.random.normal(shape=(120,)), axis=0
+      z_sample = tf.expand_dims(tf.random.normal(shape=(120,)), axis=0)
                                
     song_map = self.decoder(z_sample)
     return song_map