Answer :
The list's valid index is 4.
Describe list.
A list or series is an abstract data type in computer science that contains a finite number consecutive ordered values with the possibility of multiple occurrences of the same value. A list's (possibly) endless counterpart, a stream, is a computer depiction of the mathematical notion of a singleton or finite sequence. Because they contain other values, lists serve as a fundamental illustration of a container. If the same value appears more than once, each occurrence is regarded as a separate item. Linked lists and arrays are two other defined data formats that may be used to construct abstract lists that also use the name list.
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