slice

class slice(start [,stop] [,step=None])

Returns a slice object representing the set of indices (built-in).

start	??
stop	optional
step	optional

REMARKS

* This is a built-in function.
* The start and step arguments default to None. Slice objects have read-only data attributes start, stop, and step which merely return the argument values (or their default).
* They have no other explicit functionality; however, they are used by NumPy and other third-party packages.
* Slice objects are also generated when extended indexing syntax is used. For example: a[start:stop:step] or a[start:stop, i]. See itertools.islice() for an alternate version that returns an iterator.
* For the Official documentation refer to python.org

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