Issue with MXNet Getting Started Crash Course

I have a question regarding the tutorial “Getting Started/Crash Course/Train the neural network” (https://mxnet.apache.org/api/python/docs/tutorials/getting-started/crash-course/4-train.html), cell #12:
Shouldn’t the line
train_loss += loss.mean().asscalar()
be replaced by
train_loss += loss.sum().asscalar()?