How to report abondand URL in example code

Since I’m new to the Mxnet, for the first lesson I encounter an error message when follow the instruction
https://cv.gluon.ai/build/examples_classification/demo_cifar10.html#sphx-glr-download-build-examples-classification-demo-cifar10-py

the demo code contains a URL for example picture, which is no longer Valid, although I can manage to get the picture by search on internet, I just want to let the author know to change it to correct one, it may make freshman free easy to run their first code without to debug the error message .

The URL in codes must be fixed by someone, it starts working.