Slicing in python

Goal

A slicing selects a range of items in a sequence object (e.g., a string, tuple or list).

General syntax

a[start:stop] : from start through stop-1
a[start:] : from start through the end of the array
a[:stop] : from the beginning through stop-1
a[:] : the whole array

The negative syntax

With sequences, we can use negative syntax such as:
a[-1] : last item in the array
In the slicing location, we can also use this syntax.
start or stop may be a negative number, which means it counts from the end of the array instead of the beginning.
example:
a[:-1] : All but the last element
a[1:-1] : From the second element to the before last element
a[-2:] : last two items
a[:-5] : All but the last 5 items