NameError                                 Traceback (most recent call last)
 in 
21
22 # 학습용 이미지를 무작위로 가져오기
—> 23 dataiter = iter(trainloader)
24 images, labels = dataiter.next()
25
NameError: name ‘trainloader’ is not defined
This is a full error message. Pleae help.