You are escaping the symbols and in this case you actually don’t want to. The directions show a urlpath example with no escape codes.
So for your example link you tried to make, the following would be the correct one:
https://mybinder.org/v2/gh/pdeitel/IntroToPython/master?urlpath=lab/tree/examples/ch05/snippets_ipynb/05_02.ipynb
And that works in freshly-opened Firefox that I never use otherwise. (See discussion below in reply to @manics response.)
However, I think behind-the-scenes this employs JupyterLab’s workspaces to work and those may be broken at present. (BUT MAY NOT BE IF YOU TRY FRESH MACHINE OR BROWSER? See rest of this discussion chain below before you read the rest of this reply about rolling back.) For example, the example here doesn’t work. So it isn’t you. This is the example link that is underlying the launch binder badge:
http://mybinder.org/v2/gh/binder-examples/jupyterlab/master?urlpath=lab/tree/index.ipynb
If you try that, you’ll see it doesn’t work at present. I posted about this issue work workspaces being broken here and that contains the link to the issue that still appears to be open at present. I also posted about here. In that case, the person was able to roll back to JupyterLab 2 editing a Dockerfile. You should be able to specify the JupyterLab version in a requirements.txt configuration file, for example see here. I haven’t checked if that allows workspaces to work via MyBinder if you roll back to JupyterLab 2 (or earlier version of 3?) like as done here.