is there any way to prevent side effects in python?

Question

Is there any way to prevent side effects in python? For example, the following function has a side effect, is there any keyword or any other way to have the python complain abou

Answer 1

No, but with you example, you could use immutable types, and pass tuple as an a argument. Side effects can not affect immutable types, for example you can not append to tuple, you could only create other tuple by extending given.

UPD: But still, your function could change objects which is referenced by your immutable object (as it was pointed out in comments), write to files and do some other IO.