If you search on the forum, you will see almost everyone has this problem. Some of them solved by removing the empty line in the google download file.
If you really want people to help you, upload your google download file and show us the output of the notebook.
If you want to give up, just download different kind of bear picture( 50 images per each kind), put them into different folder in different kind, and upload them to colab or notebook folder. You will find out this way save a lot of time than trying to solve the google download url problem.
I have this problem too.
The txt file is empty. Nothing in there.