Sequence Types -- Python library reference

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2.1.5. Sequence Types

There are three sequence types: strings, lists and tuples. Strings literals are written in single quotes: 'xyzzy'. Lists are constructed with square brackets, separating items with commas: [a, b, c]. Tuples are constructed by the comma operator (not within square brackets), with or without enclosing parentheses, but an empty tuple must have the enclosing parentheses, e.g., a, b, c or (). A single item tuple must have a trailing comma, e.g., (d,). Sequence types support the following operations (s and t are sequences of the same type; n, i and j are integers):

Operation: Result --- Notes
len(s): length of s
min(s): smallest item of s
max(s): largest item of s
x in s: 1 if an item of s is equal to x, else 0
x not in s: 0 if an item of s is equal to x, else 1
s + t: the concatenation of s and t
s * n, n * s: n copies of s concatenated
s[i]: i'th item of s, origin 0 --- (1)
s[i:j]: slice of s from i to j --- (1), (2)

Notes:

(1): If i or j is negative, the index is relative to the end of the string, i.e., len(s) + i or len(s) + j is substituted. But note that -0 is still 0.
(2): The slice of s from i to j is defined as the sequence of items with index k such that i <= k < j. If i or j is greater than len(s), use len(s). If i is omitted, use 0. If j is omitted, use len(s). If i is greater than or equal to j, the slice is empty.

2.1.5. Sequence Types

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