I'm sorry. Of course.

Use spoiler flag next time, please.

W

Thanks for the feedback! I agree that returning 0 for an invalid data type can be ambiguous, since it masks the difference between the actual value of 0 and the error. Indeed, it is better to explicitly signal the error so that the user understands that something went wrong.

Disagree. How would we tell then if the sum of our array was actually zero or if it was an error?

sum_array([0, 2, -1, -1]) == sum_array(sum_array) # ??? No thanks

The better way to handle this is to raise an error, or rather in this case just let the error that already exists be raised

Since the print function returns None, it is more logical to return zero if the type is incorrect.