Is there a general way to traverse and replace the items in a nested sequence of arbitrary depth? Say, for instance, that I want to eliminate all the ...

For example the Python interpreter cannot understand your code if your indentation is off, which teaches you to write well-formatted, readable code.

You're taking a new programming class this fall, and you don't know anything about code. Python is taught widely in schools, and it's one of the most loved programming languages because it's simple.