I wonder if I can make an ASCII picture out of it... More

I wonder if sum([[1], [2], [3]], []) -> [1, 2, 3] is a side effect or an expected behavior of sum()? The docstring says that the it expects _numbers_ in the iterable: >Return the sum of an iterable of numbers (NOT strings) plus the value of parameter 'start' (which defaults to 0). I More