It is a little confusing. Regarding the example, this may help a bit. I don't think it's a spoiler.
maxSequence([-2, 1, -3, (4, -1, 2, 1,) -5, 4])

Thanks a lot!

This one I don't get! The last line, how does it work, I understand what it does, but I don't get the syntax? Can author(or someone else) be so kind to enlighten me, please!

I tried to solve it like this, but i've got an error.
Because it doesn't solve the \n problem, and when I solved that problem, the error again forced me to put \ in front of ' also, to pass?!
So something's buggy with this one.