Colon (:) in Python list index
python
Solution
`:` is the delimiter of the slice syntax to 'slice out' sub-parts in sequences , `[start:end]`
[1:5] is equivalent to "from 1 to 5" (5 not included)
[1:] is equivalent to "1 to end"
[len(a):] is equivalent to "from length of a to end"
Watch https://youtu.be/tKTZoB2Vjuk?t=41m40s at around 40:00 he starts explaining that.
Works with tuples and strings, too.
Problem
I'm new to Python. I see `:` used in list indices especially when it's associated with function calls. Python 2.7 documentation suggests that `lists.append` translates to `a[len(a):] = [x]`. Why does one need to suffix `len(a)` with a colon? I understand that `:` is used to identify keys in dictionary.