Are application assignments in Datascience common practice?

this might seem off topic, but I hope this question will be tolerated.

I was recently asked to help a friend with an assignment in the process of applying for a new job as data scientist. And honestly I had a lot of fun solving the assignment for me and giving him guidance on how to proceed

However this got me wondering about a few things:

• is it common practice in Datascience to hand out assignments to applicants?

• is there a database available with datascience assignments, because I enjoy doing them?