These represent finite ordered sets indexed by nonnegative numbers. The builtin function len()
returns the number of items of a sequence. When the length of a sequence is n
, the index set contains the numbers 0, 1, ..., n1
. Item i
of sequence a is selected by a[i]
.
Python Docs  Standard Type Hierarchy
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Builtin sequence types are:
list
tuple
range

Builtin sequence types are iterable types (implement required
__iter__()
method). 
Operations: