Sentinel
Language: Slices
Slices are an efficient way to create a substring or sublist from an existing string or list, respectively.
The syntax for creating a slice is:
a[low : high]
low is the lowest index to slice from. The resulting slice includes
the value at low. high is the index to slice to. The resulting slice
will not include the value at high. The length of the resulting list
or string is always high - low.
a = [1, 2, 3, 4, 5]
b = a[1:4] // [2, 3, 4]
a = "hello"
b = a[1:4] // "ell"