To my knowledge, indexing with -1 will bring you up the last item in a list e.g.
list = 'ABCDEFG'
list[-1]
'G'
But when you are asking for a sequence from the list, -1 gives the second to last term in a list,
list[3:-1]
'DEF'
Why? I would have expected, and would like to get DEFG
It is because the stop (second) argument of slice notation is exclusive, not inclusive. So, [3:-1] is telling Python to get everything from index 3 up to, but not including, index -1.
To get what you want, use [3:]:
>>> list = 'ABCDEFG'
>>> list[3:]
'DEFG'
>>>
>>> list[3:len(list)] # This is equivalent to doing: list[3:]
'DEFG'
>>>
Also, just a note for the future: it is considered a bad practice to use list as a variable name. Doing so overshadows the built-in.
It's for the same reason that list[3:4] doesn't include the character at the 4th index; slicing is not inclusive. In addition, you can slice from a character to the end simply by omitting the second slice parameter, as in list[3:].
